Interior train components having low smoke and low heat release, and methods of their manufacture

ABSTRACT

Seat components and claddings for railway molded or formed from a thermoplastic polymer composition comprising, based on the total weight of the composition, 50 to 93 wt. % of a specific polycarbonate; 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units; 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; wherein an article having a thickness of 0.5 to 10 mm molded from the composition has a Ds-4 smoke density ≦300 measured according to ISO 5659-2, and a MAHRE ≦90 kW/m 2  measured according to ISO 5660-1, a multiaxial impact energy ≧100 J, and a ductility in multiaxial impact of 80 to 100% at +23° C. according to ISO 6603.

BACKGROUND

This disclosure is directed to components for the interior of trains, and in particular seat components and claddings having low smoke density and low heat release.

Standards for flame retardancy properties such as flame spread, heat release, and smoke generation upon burning have become increasingly stringent for articles used in mass transportation such as trains. The European Union has approved the introduction of a new harmonized fire standard for rail applications, namely EN-45545, to replace all currently active different standards in each member state. This standard imposes stringent requirements on heat release, smoke density, and toxicity and flame spread properties allowed for materials used in these applications. Smoke density (Ds-4) in EN-45545 is the smoke density after four minutes measured according to ISO 5659-2, and heat release in EN-45545 is the maximum average rate of heat emission (MAHRE) measured according to ISO5660-1 and flame spread in EN-45545 is the critical heat flux at extinguishment (CFE) measured according to ISO 5658-2.

“Hazard Levels” (HL1 to HL3) have been designated, reflecting the degree of probability of personal injury as the result of a fire. The levels are based on dwell time and are related to operation and design categories. HL1 is the lowest hazard level and is typically applicable to vehicles that run under relatively safe conditions (easy evacuation of the vehicle). HL3 is the highest hazard level and represents most dangerous operation/design categories (difficult and/or time-consuming evacuation of the vehicle, e.g. in underground rail cars). For each application type, different test requirements for the hazard levels are defined.

For R6 applications, covering seat components, requirements on smoke density after four minutes measured according to ISO 5659-2 (Ds-4) are Ds-4 values at or below 300 measured at 50 kW/m² for HL2 and at or below 150 measured at 50 kW/m² for HL3. Requirements on the maximum average rate of heat emission (MAHRE) measured according to ISO5660-1 are at or below 90 kW/m² determined at 50 kW/m² for HL2 and at or below 60 kW/m² determined at 50 kW/m² for HL3. For R6 applications, no requirements on flame spread measured according to ISO 5658-2 exist.

Typical applications falling under R1 applications include interior vertical surfaces, such as side walls, front walls, end-walls, partitions, room dividers, flaps, boxes, hoods and louvres; interior doors and linings for internal and external doors; window insulations, kitchen interior surfaces, interior horizontal surfaces, such as ceiling paneling, flaps, boxes, hoods and louvres; luggage storage areas, such as overhead and vertical luggage racks, luggage containers and compartments; driver's desk applications, such as paneling and surfaces of driver's desk; interior surfaces of gangways, such as interior sides of gangway membranes (bellows) and interior linings; window frames (including sealants and gaskets); (folding) tables with downward facing surface; interior and exterior surface of air ducts, and devices for passenger information (such as information display screens). For R1 applications, requirements on smoke density after four minutes measured according to ISO 5659-2 (Ds-4) are Ds-4 values at or below 300 measured at 50 kW/m² for HL2 and at or below 150 measured at 50 kW/m² for HL3. Requirements on the maximum average rate of heat emission (MAHRE) measured according to ISO5660-1 are at or below 90 kW/m² determined at 50 kW/m² for HL2 and at or below 60 kW/m² determined at 50 kW/m² for HL3. Requirements on the critical heat flux at extinguishment (CFE) measured according to ISO 5658-2 are at or above 20 kW/m² for both HL2 and HL3.

It is exceptionally challenging to manufacture interior articles for trains that meet stringent smoke density standards, heat release standards and/or flame spread standards in addition to other material requirements. It is particularly challenging manufacture articles that meet these standards and that have good mechanical properties (especially impact/scratch resistance) and processability. Accordingly there remains a need for interior articles for trains, and in particular seat components and claddings that have a combination of low smoke, low heat release, and low flame spread properties. It would be a further advantage if the articles could be rendered low smoke and low heat release without a significant detrimental effect on one or more of material cost, manufacturing ease, and mechanical properties. It would be a still further advantage if the materials could be readily thermoformed or injection molded. It would still be a further advantage if such materials could be manufactured to be colorless and transparent. It would be a still further advantage if such materials were in compliance with European Railway standard EN-45545, for example, without having a detrimental effect on material cost, ease of manufacture, and mechanical properties.

SUMMARY

Disclosed herein is a railway component wherein the component is a seat component, and wherein the railway component is molded or formed from a thermoplastic polymer composition comprising, based on the total weight of the composition, 50 to 93 wt. % of a poly(bisphenol A carbonate)-co-(bisphenol phthalate ester); 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E has an average value of 2 to 200, wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein an article having a thickness of 0.5 to 10 mm molded from the composition has a Ds-4 smoke density of less than or equal to 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², and a MAHRE of less than or equal to 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², a multiaxial impact energy at or above 100 J and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs, and optionally, a melt volume flow rate of greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133.

In a specific embodiment, the composition comprises 4 to 20 wt. % of the poly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm. These transparencies can be achieved by use of a poly(carbonate-siloxane) comprising carbonate units derived from bisphenol A, and repeating siloxane units, wherein the siloxane units have an average value of 4 to 50, 4 to 15, specifically 5 to 15, more specifically 6 to 15, and still more specifically 7 to 10. The transparent poly(carbonate-siloxane) can be manufactured using one or both of the tube reactor processes described in U.S. Patent Application No. 2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 may be used to synthesize the poly(siloxane-carbonate) copolymers.

Also disclosed herein is a railway component wherein the component is a seat component, and wherein the railway component is molded or formed from a thermoplastic polymer composition comprising 50 to 93 wt. % of a polycarbonate copolymer comprising bisphenol A carbonate units and units of the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to five C₁₋₁₀ alkyl groups, or C₁₋₄ alkyl; 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E has an average value of 2 to 200, wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein an article having a thickness of 0.5 to 10 mm molded from the composition has a Ds-4 smoke density of less than or equal to 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², and a MAHRE of less than or equal to 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², a multiaxial impact energy at or above 100 J and a ductility of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs, and optionally, a melt volume flow rate of greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133.

In a specific embodiment, the composition comprises 4 to 20 wt. % of the poly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm. These transparencies can be achieved by use of a PC-siloxane comprising carbonate units derived from bisphenol A, and repeating siloxane units, wherein the siloxane units have an average value of 4 to 50, 4 to 15, specifically 5 to 15, more specifically 6 to 15, and still more specifically 7 to 10. The transparent PC-siloxanes can be manufactured using one or both of the tube reactor processes described in U.S. Patent Application No. 2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 may be used to synthesize the poly(siloxane-carbonate) copolymers.

Also described herein is a railway component wherein the component is an interior vertical surface, such as side walls, front walls, end-walls, partitions, room dividers, flaps, boxes, hoods and louvres; an interior door or lining for internal and external doors; a window insulation, a kitchen interior surface, an interior horizontal surface, such as ceiling paneling, flaps, boxes, hoods and louvres; a luggage storage area, such as overhead and vertical luggage racks, luggage containers and compartments; a driver's desk application, such as paneling and surfaces of driver's desk; an interior surface of gangways, such as interior sides of gangway membranes (bellows) and interior linings; a window frame (including sealants and gaskets); a (folding) table with downward facing surface; an interior or exterior surface of air ducts, or a device for passenger information, such as information display screens, and wherein the railway component is molded or formed from a thermoplastic polymer composition comprising 50 to 93 wt. % of a poly(bisphenol A carbonate)-co-(bisphenol phthalate ester); 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E has an average value of 2 to 200, wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein an article having a thickness of 0.5 to 10 mm molded from the composition has a Ds-4 smoke density of less than or equal to 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², and a MAHRE of less than or equal to 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², a critical heat flux at extinguishment (CFE) of equal to or more than 20 kW/m² measured according to ISO 5658-2 at a 3 mm thick plaque, a multiaxial impact energy at or above 100 J and a ductility of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs, and optionally, a melt volume flow rate of greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133.

In a specific embodiment, the composition comprises 4 to 20 wt. % of the poly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm. These transparencies can be achieved by use of a PC-siloxane comprising carbonate units derived from bisphenol A, and repeating siloxane units, wherein the siloxane units have an average value of 4 to 50, 4 to 15, specifically 5 to 15, more specifically 6 to 15, and still more specifically 7 to 10. The transparent PC-siloxanes can be manufactured using one or both of the tube reactor processes described in U.S. Patent Application No. 2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 may be used to synthesize the poly(siloxane-carbonate) copolymers.

Also described herein is a railway component wherein the component is an interior vertical surface, such as side walls, front walls, end-walls, partitions, room dividers, flaps, boxes, hoods and louvres; an interior door or lining for internal and external doors; a window insulation, a kitchen interior surface, an interior horizontal surface, such as ceiling paneling, flaps, boxes, hoods and louvres; a luggage storage area, such as overhead and vertical luggage racks, luggage containers and compartments; a driver's desk application, such as paneling and surfaces of driver's desk; an interior surface of gangways, such as interior sides of gangway membranes (bellows) and interior linings; a window frame (including sealants and gaskets); a (folding) table with downward facing surface; an interior or exterior surface of air ducts, or a device for passenger information, such as information display screens, and wherein the railway component is molded or formed from a thermoplastic polymer composition comprising, based on the total weight of the composition, 50-93 wt. % of a polycarbonate copolymer comprising bisphenol A carbonate units and units of the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to five C₁₋₁₀ alkyl groups, or C₁₋₄ alkyl; 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E has an average value of 2 to 200, wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein an article having a thickness of 0.5 to 10 mm molded from the composition has a Ds-4 smoke density of less than or equal to 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², and a MAHRE of less than or equal to 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², a critical heat flux at extinguishment (CFE) of equal to or more than 20 kW/m² measured according to ISO 5658-2 at a 3 mm thick plaque, a multiaxial impact energy at or above 100 J and a ductility of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs, and optionally, a melt volume flow rate of greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133.

In a specific embodiment, the composition comprises 4 to 20 wt. % of the poly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm. These transparencies can be achieved by use of a PC-siloxane comprising carbonate units derived from bisphenol A, and repeating siloxane units, wherein the siloxane units have an average value of 4 to 50, 4 to 15, specifically 5 to 15, more specifically 6 to 15, and still more specifically 7 to 10. The transparent PC-siloxanes can be manufactured using one or both of the tube reactor processes described in U.S. Patent Application No. 2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 may be used to synthesize the poly(siloxane-carbonate) copolymers.

Further described as a railway component that is a molded or extruded train seat component or cladding comprising a thermoplastic composition comprising, based on the total weight of the composition: 50 to 93 wt. % of combination comprising (i) 5 to 50 wt. % of bisphenol A polycarbonate and (ii) 50 to 95 wt. % of a poly(bisphenol arylate) of the formula

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, C₁₋₁₂ alkenyl, C₃₋₈ cycloalkyl, or C₁₋₁₂ alkoxy, p and q are each independently 0 to 4, and X^(a) is a bridging group between the two arylene groups, and is a single bond, —O—, —S—, —S(O)—, —S(O)₂—, —C(O)—, a C₁₋₁₁ alkylidene of the formula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independently hydrogen or C₁₋₁₀ alkyl, or a group of the formula —C(═R^(e))— wherein R^(e) is a divalent C₁₋₁₀ hydrocarbon group, based on the weight of the combination; and siloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E has an average value of 2 to 200, wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein the component has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs.

In a specific embodiment, the composition comprises 4 to 20 wt. % of the poly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm. These transparencies can be achieved by use of a PC-siloxane comprising carbonate units derived from bisphenol A, and repeating siloxane units, wherein the siloxane units have an average value of 4 to 50, 4 to 15, specifically 5 to 15, more specifically 6 to 15, and still more specifically 7 to 10. The transparent PC-siloxanes can be manufactured using one or both of the tube reactor processes described in U.S. Patent Application No. 2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 may be used to synthesize the poly(siloxane-carbonate) copolymers.

In yet another embodiment, a method of manufacture of the railway component comprises molding or extruding the above-described compositions to form the component.

The above described and other features are exemplified by the following Figures, Detailed Description, and Examples.

BRIEF DESCRIPTION OF THE DRAWINGS

A description of the figures, which are meant to be exemplary and not limiting, is provided in which:

FIG. 1 shows the effect of the SiPC2 content in PPP-BP/BPA on smoke density (Ds-4);

FIG. 2 shows the effect of the silicon content in PPP-BP/BPA on smoke density (Ds-4);

FIG. 3 shows the effect of the content of SiPC2 in PC-Ester1 on smoke density (Ds-4);

FIG. 4 shows the effect of the silicon content from various polycarbonate-siloxane copolymers in PC-Ester1 on smoke density (Ds-4); and

FIG. 5 shows the effect of the silicon content from various polysiloxanes in PC-Ester1 on smoke density (Ds-4).

DETAILED DESCRIPTION

The inventors hereof have developed articles for use in train interiors, including seat components and claddings. The articles have low smoke density characteristics, in particular Ds-4 measured according to ISO5659-2, and low heat release characteristics, in particular improved MAHRE measured according to ISO5660-1, and can unexpectedly be obtained by use of specific thermoplastic polycarbonate compositions. Thus, it has been discovered that the addition of the small amount of poly(carbonate-siloxane) copolymer, a polydialkylsiloxane, or a combination comprising at least one of the foregoing to poly(bisphenol A carbonate)-co-(bisphenol phthalate esters) or polycarbonate copolymer comprising bisphenol A carbonate units and units of the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to five C₁₋₁₀ alkyl groups, or C₁₋₄ alkyl; results in a significant decrease in the smoke density (Ds-4) of the polycarbonate polymers measured according to ISO 5659-2.

The results are particularly surprising because neither polycarbonate polymers alone nor poly(carbonate-siloxane) copolymers alone have a good performance in the ISO5659 smoke density test. For example, most polycarbonate polymers have DS-4 values far exceeding 480 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², and poly(carbonate-siloxane) copolymers and polydialkylsiloxanes can have DS-4 values greater than 1,000 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m². However, the combination of the polycarbonate polymer and the poly(carbonate-siloxane) copolymer, polydialkylsiloxane, or a combination comprising at least one of the foregoing, and an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition, results in a composition having DS-4 values below 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m². The compositions also have low heat release with MAHRE values below 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m².

Furthermore, the results are surprising because it is discovered that only polysiloxanes with alkyl siloxane groups, for example, polydimethylsiloxane, are capable of reducing smoke density of a polycarbonate polymer, whereas polysiloxanes containing phenyl siloxane units (only phenyl siloxane or combined with alkyl siloxane) are even detrimental for smoke density. This is highly unexpected, as for other flame properties, such as UL V-0 compliance, the siloxane of choice is typically phenyl based siloxane such as octaphenylcyclotetrasiloxane or polyphenylmethylsiloxane rather than polydialkylsiloxanes such as polydimethylsiloxane.

With this discovery, it is now possible to manufacture seat components and claddings having the required low smoke densities (Ds-4) measured according to ISO5659-2 on 3 mm thick samples at 50 kW/m² and low heat release (MAHRE) measured according to ISO 5660-1 on 3 mm thick samples at 50 kW/m² and optionally low flame spread measured according to ISO 5658-2.

The polycarbonate compositions can further have excellent impact strength. The polycarbonate compositions can also be formulated to have low melt viscosities, which renders them suitable for injection molding. Such compositions are especially useful in the manufacture of seat components and claddings. The compositions can further have very high transmission and low haze which makes it possible to manufacture transparent or diffusive seat components and claddings. In particular, the seat components and claddings molded or extruded from polycarbonate compositions containing a first polycarbonate selected from poly(bisphenol A carbonate)-co-(bisphenol phthalate esters) or polycarbonate copolymer comprising bisphenol A carbonate units and units of the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to five C₁₋₁₀ alkyl groups, or C₁₋₄ alkyl; and a second polymer different from the first polycarbonate, the second polymer comprising a poly(carbonate-siloxane) copolymer, a polydialkylsiloxane, or a combination comprising at least one of the foregoing, and an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; wherein an article molded from the first polycarbonate has a smoke density after 4 minutes (DS-4) of greater than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m²; an article molded from the second polymer has a smoke density after 4 minutes (DS-4) of greater than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m²; and an article molded from the composition has a smoke density after 4 minutes (DS-4) of smaller than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², low heat release with MAHRE values below 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m² and optionally low flame spread with CFE values above 20 kW/m² measured according to ISO 5658-2.

In a particularly advantageous feature, the thermoplastic compositions can have very low smoke density with Ds-4 values at or below 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a low maximum average heat release (MAHRE) at or below 90 kJ/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², while allowing sufficient melt flow for injection molding of relatively large parts, while simultaneously retaining sufficient practical impact resistance characteristics. Optionally, the compositions can have a critical heat flux at extinguishment (CFE) at or above 20 kW/m² measured according to ISO 5658-2 on a 3 mm thick plaque. Furthermore, these compositions can have a transmission of 80% or more or a haze of 5 or less, each measured using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3.2 mm measured according to ASTM D1003.

As used herein, the term “polycarbonate” and “polycarbonate polymer” refers to compounds having first repeating first units that are bisphenol carbonate units of formula (1)

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, C₁₋₁₂ alkenyl, C₃₋₈ cycloalkyl, or C₁₋₁₂ alkoxy, p and q are each independently 0 to 4, and X^(a) is a bridging group between the two arylene groups, and is a single bond, —O—, —S—, —S(O)—, —S(O)₂—, —C(O)—, a C₁₋₁₁ alkylidene of the formula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independently hydrogen or C₁₋₁₀ alkyl, or a group of the formula —C(═R^(e))— wherein R^(e) is a divalent C₁₋₁₀ hydrocarbon group. Exemplary X^(a) groups include methylene, ethylidene, neopentylidene, and isopropylidene. The bridging group X^(a) and the carbonate oxygen atoms of each C₆ arylene group can be disposed ortho, meta, or para (specifically para) to each other on the C₆ arylene group.

In a specific embodiment, R^(a) and R^(b) are each independently a C₁₋₃ alkyl group, p and q are each independently 0 to 1, and X^(a) is a single bond, —O—, —S(O)—, —S(O)₂—, —C(O)—, a C₁₋₉ alkylidene of formula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independently hydrogen or C₁₋₈ alkyl, or a group of the formula —C(═R^(e))— wherein R^(e) is a divalent C₁₋₉ hydrocarbon group. In another specific embodiment, R^(a) and R^(b) are each independently a methyl group, p and q are each independently 0 to 1, and X^(a) is a single bond, a C₁₋₇ alkylidene of formula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independently hydrogen or C₁₋₆ alkyl. In an embodiment, p and q is each 1, and R^(a) and R^(b) are each a C₁₋₃ alkyl group, specifically methyl, disposed meta to the oxygen on each ring. The bisphenol carbonate units (1) can be derived from bisphenol A, where p and q are both 0 and X^(a) is isopropylidene.

The polycarbonate units in the copolymers can be produced from dihydroxy compounds of the formula (2)

HO—R¹—OH  (2)

wherein R¹ is a bridging moiety. Thus, the bisphenol carbonate units (1) are generally produced from the corresponding bisphenol compounds of formula (3)

wherein Ra and R^(b), p and q, and X^(a) are the same as in formula (1).

Some illustrative examples of specific bisphenol compounds that can be used to produce units (1) include 4,4′-dihydroxybiphenyl, bis(4-hydroxyphenyl)methane, 1,2-bis(4-hydroxyphenyl)ethane, 2-(4-hydroxyphenyl)-2-(3-hydroxyphenyl)propane, 1,2,2-bis(3-methyl-4-hydroxyphenyl)propane, 2,2-bis(3-ethyl-4-hydroxyphenyl)propane, 2,2-bis(3-n-propyl-4-hydroxyphenyl)propane, 2,2-bis(3-isopropyl-4-hydroxyphenyl)propane, 2,2-bis(3-sec-butyl-4-hydroxyphenyl)propane, 2,2-bis(3-t-butyl-4-hydroxyphenyl)propane, 2,2-bis(3-cyclohexyl-4-hydroxyphenyl)propane, 2,2-bis(3-allyl-4-hydroxyphenyl)propane, 2,2-bis(3-methoxy-4-hydroxyphenyl)propane, bis(4-hydroxyphenyl)ether, bis(4-hydroxyphenyl)sulfide, bis(4-hydroxyphenyl)sulfoxide, bis(4-hydroxyphenyl)sulfone, or a combination comprising at least one of the foregoing bisphenolic compounds.

Specific examples of bisphenol compounds that can be used in the production of bisphenol carbonate units (1) include 1,1-bis(4-hydroxyphenyl) methane, 1,1-bis(4-hydroxyphenyl) ethane, 2,2-bis(4-hydroxyphenyl) propane (“bisphenol A” or “BPA”), 2,2-bis(4-hydroxyphenyl) butane, 2,2-bis(4-hydroxyphenyl) octane, 1,1-bis(4-hydroxyphenyl) propane, 1,1-bis(4-hydroxyphenyl) n-butane, 2,2-bis(4-hydroxy-2-methylphenyl) propane, 1,1-bis(4-hydroxy-t-butylphenyl) propane, and combinations comprising at least one of the foregoing bisphenol compounds.

The polycarbonate polymer can be a copolymer that further comprises second repeating units. The second repeating units can be bisphenol carbonate units (provided that they are different from the bisphenol carbonate units (1)), or arylate ester units. In particular, the second units can be bisphenol carbonate units of formula (4)

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkenyl, C₃₋₈ cycloalkyl, or C₁₋₁₂ alkoxy, p and q are each independently integers of 0 to 4, and X^(b) is C₂₋₃₂ bridging hydrocarbon group that is not the same as the X^(a) in the polycarbonate copolymer. The bridging group X^(b) and the carbonate oxygen atoms of each C₆ arylene group can be disposed ortho, meta, or para (specifically para) to each other on the C₆ arylene group.

In an embodiment, X^(b) is a substituted or unsubstituted C₃₋₁₈ cycloalkylidene, a substituted or unsubstituted C₃₋₁₈ cycloalkylene, a substituted or unsubstituted C₁₂₋₂₅ alkylidene of formula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independently hydrogen, C₁₋₂₄ alkyl, C₄₋₁₂ cycloalkyl, C₆₋₁₂ aryl, C₇₋₁₂ arylalkylene, C₁₋₁₂ heteroalkyl, or cyclic C₇₋₁₂ heteroarylalkyl, or a group of the formula —C(═R^(e))— wherein R^(e) is a divalent C₁₂₋₃₁ hydrocarbon group. Exemplary X^(b) groups include cyclohexylmethylidene, 1,1-ethene, 2-[2.2.1]-bicycloheptylidene, cyclohexylidene, cyclopentylidene, cyclododecylidene, and adamantylidene.

In an embodiment, X^(b) is a substituted or unsubstituted C₅₋₃₂ alkylidene of formula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independently hydrogen, C₄₋₁₂ cycloalkyl, C₆₋₁₂ aryl, C₇₋₁₂ arylalkylene, C₁₋₁₂ heteroalkyl, a substituted or unsubstituted group of the formula —C(═R^(e))— wherein R^(e) is a divalent C₁₂₋₃₁ hydrocarbyl, a substituted or unsubstituted C₅₋₁₈ cycloalkylidene, a substituted or unsubstituted C₅₋₁₈ cycloalkylene, a substituted or unsubstituted C₃₋₁₈ heterocycloalkylidene, or a group of the formula —B¹-G-B²- wherein B¹ and B² are the same or different C₁₋₆ alkylene group and G is a C₃₋₁₂ cycloalkylidene group or a C₆₋₁₆ arylene group.

For example, X^(b) can be a substituted C₃₋₁₈ heterocycloalkylidene of formula (4a)

wherein R^(r), R^(p), R^(q), and R^(t) are each independently hydrogen, oxygen, or C₁₋₁₂ organic groups; I is a direct bond, a carbon, or a divalent oxygen, sulfur, or —N(Z)— where Z is hydrogen, halogen, hydroxy, C₁₋₁₂ alkyl, C₁₋₁₂ alkoxy, or C₁₋₁₂ acyl; h is 0 to 2, j is 1 or 2, i is an integer of 0 or 1, and k is an integer of 0 to 3, with the proviso that at least two of R^(r), R^(p), R^(q), and R^(t) taken together are a fused cycloaliphatic, aromatic, or heteroaromatic ring. It will be understood that where the fused ring is aromatic, the ring as shown in formula (3) will have an unsaturated carbon-carbon linkage where the ring is fused. When k is one and i is 0, the ring as shown in formula (6) contains 4 carbon atoms, when k is 2, the ring contains 5 carbon atoms, and when k is 3, and the ring contains 6 carbon atoms. In an embodiment, two adjacent groups (e.g., R^(q) and R^(t) taken together) form an aromatic group, and in another embodiment, R^(q) and R^(t) taken together form one aromatic group and R^(r) and R^(p) taken together form a second aromatic group. When R^(q) and R^(t) taken together form an aromatic group, R^(p) can be a double-bonded oxygen atom, i.e., a ketone.

Specific second bisphenol carbonate repeating units of this type are phthalimidine carbonate units of formula (4b)

wherein R^(a), R^(b), p, and q are as in formula (4), R³ is each independently a C₁₋₆ alkyl, j is 0 to 4, and R⁴ is hydrogen, C₁₋₆ alkyl, phenyl optionally substituted with 1 to 5 C₁₋₆ alkyl groups. In an embodiment, R^(a) and R^(b) are each independently C₁₋₃ alkyl. For example, the phthalimidine carbonate units are of formula (4c)

wherein R⁵ is hydrogen, phenyl optionally substituted with up to five C₁₋₆ alkyl groups, or C₁₋₄ alkyl. In an embodiment, R⁵ is hydrogen, phenyl, or methyl. Carbonate units (4c) wherein R⁵ is phenyl can be derived from 2-phenyl-3,3′-bis(4-hydroxy phenyl)phthalimidine (also known as N-phenyl phenolphthalein bisphenol, or “PPP-BP”) (also known as 3,3-bis(4-hydroxyphenyl)-2-phenylisoindolin-1-one).

Other bisphenol carbonate repeating units of this type are the isatin carbonate units of formula (4d) and (4e)

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, p and q are each independently 0 to 4, and R^(i) is C₁₋₁₂ alkyl, phenyl optionally substituted with 1 to 4 C₁₋₁₀ alkyl groups, or benzyl optionally substituted with 1 to 5 C₁₋₁₀ alkyl groups. In an embodiment, R^(a) and R^(b) are each methyl, p and q are each independently 0 or 1, and R^(i) is C₁₋₄ alkyl or phenyl.

Examples of bisphenol carbonate units (4) wherein X^(b) is a substituted or unsubstituted C₃₋₁₈ cycloalkylidene include the cyclohexylidene-bridged, alkyl-substituted bisphenol of formula (4f)

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, R^(g) is C₁₋₁₂ alkyl, p and q are each independently 0 to 4, and t is 0 to 10. In a specific embodiment, at least one of each of R^(a) and R^(b) are disposed meta to the cyclohexylidene bridging group. In an embodiment, R^(a) and R^(b) are each independently C₁₋₄ alkyl, R^(g) is C₁₋₄ alkyl, p and q are each 0 or 1, and t is 0 to 5. In another specific embodiment, R^(a), R^(b), and R^(g) are each methyl, r and s are each 0 or 1, and t is 0 or 3, specifically 0.

Examples of other bisphenol carbonate units (4) is a substituted or unsubstituted C₃₋₁₈ cycloalkylidene include adamantyl units of formula (4g) and fluorenyl units of formula (4h)

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, and p and q are each independently 1 to 4. In a specific embodiment, at least one of each of R^(a) and R^(b) are disposed meta to the cycloalkylidene bridging group. In an embodiment, R^(a) and R^(b) are each independently C₁₋₃ alkyl, and p and q are each 0 or 1; specifically, R^(a), R^(b) are each methyl, p and q are each 0 or 1, and when p and q are 1, the methyl group is disposed meta to the cycloalkylidene bridging group. Carbonates containing units (4a) to (4g) are useful for making polycarbonates with high glass transition temperatures (Tg) and high heat distortion temperatures.

Bisphenol carbonate units (4) are generally produced from the corresponding bisphenol compounds of formula (5)

wherein R^(a), R^(b), p, q, and X^(b) are the same as in formula (4).

Specific examples of bisphenol compounds of formula (5) include bis(4-hydroxyphenyl)diphenylmethane, 1,1-bis(4-hydroxy-t-butylphenyl) propane, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 6,6′-dihydroxy-3,3,3′,3′-tetramethylspiro(bis)indane (“spirobiindane bisphenol”), 2,6-dihydroxydibenzo-p-dioxin, 2,6-dihydroxythianthrene, 2,7-dihydroxyphenoxathiin, 2,7-dihydroxy-9,10-dimethylphenazine, 3,6-dihydroxydibenzofuran, 3,6-dihydroxydibenzothiophene, 2,7-dihydroxycarbazole, and 2,6-dihydroxythianthrene 3,3-bis(4-hydroxyphenyl) phthalimidine, 2-phenyl-3,3-bis(4-hydroxyphenyl) phthalimidine (PPP-BP), and 1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane (DMBPC). Combinations comprising at least one of the foregoing dihydroxy compounds can also be used.

The relative mole ratio of first bisphenol carbonate units (1) and second bisphenol carbonate units (4) can vary from 99:1 to 1:99, depending on the desired characteristics of the polycarbonate composition, including glass transition temperature (“Tg”), impact strength, ductility, flow, and like considerations. For example, the mole ratio of units (1): units (4) can be from 90:10 to 10:90, from 80:20 to 20:80, from 70:30 to 30:70, or from 60:40 to 40:60. When bisphenol carbonate units (1) units are derived from bisphenol A, the bisphenol A units are generally present in an amount from 50 to 99 mole %, based on the total moles of units in the polycarbonate copolymer. For example, when bisphenol carbonate units (1) are derived from bisphenol A, and bisphenol units (4) are derived from PPP-BP, the mole ration of units (1) to units (4) can be from 99:1 to 50:50, or from 90:10 to 55:45.

Other carbonate units can be present in any of the polycarbonate copolymers described herein in relatively small amounts, for example less than 20 mole %, less than 10 mole %, or less than 5 mole %, based on the total moles of units in the polycarbonate copolymer. The other carbonate units can be derived from aliphatic or aromatic dihydroxy compounds having 1 to 32 carbon atoms, for example 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 6,6′-dihydroxy-3,3,3′,3′-tetramethylspiro(bis)indane (“spirobiindane bisphenol”), 2,6-dihydroxydibenzo-p-dioxin, 2,6-dihydroxythianthrene, 2,7-dihydroxyphenoxathin, 2,7-dihydroxy-9,10-dimethylphenazine, 3,6-dihydroxydibenzofuran, 3,6-dihydroxydibenzothiophene, 2,7-dihydroxycarbazole, and 2,6-dihydroxythianthrene. A specific aromatic dihydroxy compound includes the monoaryl dihydroxy compounds of formula (6)

wherein each R^(h) is independently a halogen atom, a C₁₋₁₀ hydrocarbyl such as a C₁₋₁₀ alkyl group, a halogen-substituted C₁₋₁₀ alkyl group, a C₆₋₁₀ aryl group, or a halogen-substituted C₆₋₁₀ aryl group, and n is 0 to 4. The halogen is usually bromine. In an embodiment, no halogens are present. Specific monoaryl dihydroxy compounds (6) include resorcinol, substituted resorcinol compounds such as 5-methyl resorcinol, 5-ethyl resorcinol, 5-propyl resorcinol, 5-butyl resorcinol, 5-t-butyl resorcinol, 5-phenyl resorcinol, 5-cumyl resorcinol, 2,4,5,6-tetrafluoro resorcinol, 2,4,5,6-tetrabromo resorcinol, and the like; catechol; hydroquinone; and substituted hydroquinones such as 2-methyl hydroquinone, 2-ethyl hydroquinone, 2-propyl hydroquinone, 2-butyl hydroquinone, 2-t-butyl hydroquinone, 2-phenyl hydroquinone, 2-cumyl hydroquinone, 2,3,5,6-tetramethyl hydroquinone, 2,3,5,6-tetra-t-butyl hydroquinone, 2,3,5,6-tetrafluoro hydroquinone, 2,3,5,6-tetrabromo hydroquinone. A combination comprising at least one of the foregoing aromatic dihydroxy compounds can be used. In an embodiment, the polycarbonate copolymer comprises carbonate units of formulas (1) and (4), and less than 10 mole % of units derived from monoaryl dihydroxy compounds (6), i.e., monoaryl carbonate units of the formula (6a)

wherein each R^(h) is independently a halogen or C₁₋₁₀ hydrocarbon group, and n is 0 to 4. Specifically, each R^(h) is independently a C₁₋₃ alkyl group, and n is 0 to 1, or n is 0. In another embodiment, no carbonate units other than units of formulas (1) and (4) are present in the polycarbonate copolymer.

Polycarbonates can be manufactured by processes such as interfacial polymerization and melt polymerization. Although the reaction conditions for interfacial polymerization can vary, an exemplary process generally involves dissolving or dispersing a dihydric phenol reactant in aqueous caustic soda or potash, adding the resulting mixture to a water-immiscible solvent medium, and contacting the reactants with a carbonate precursor in the presence of a catalyst such as, for example, a tertiary amine or a phase transfer catalyst, under controlled pH conditions, e.g., 8 to 10. The water immiscible solvent can be, for example, methylene chloride, 1,2-dichloroethane, chlorobenzene, toluene, and the like.

Exemplary carbonate precursors include a carbonyl halide such as carbonyl bromide or carbonyl chloride, or a haloformate such as a bishaloformates of a dihydric phenol (e.g., the bischloroformates of bisphenol A, hydroquinone, or the like) or a glycol (e.g., the bishaloformate of ethylene glycol, neopentyl glycol, polyethylene glycol, or the like). Combinations comprising at least one of the foregoing types of carbonate precursors can also be used. In an embodiment, an interfacial polymerization reaction to form carbonate linkages uses phosgene as a carbonate precursor, and is referred to as a phosgenation reaction.

Among tertiary amines that can be used are aliphatic tertiary amines such as triethylamine and tributylamine, cycloaliphatic tertiary amines such as N,N-diethyl-cyclohexylamine, and aromatic tertiary amines such as N,N-dimethylaniline. Among the phase transfer catalysts that can be used are catalysts of the formula (R³)₄Q⁺X⁻, wherein each R₃ is the same or different, and is a C₁₋₁₀ alkyl group; Q is a nitrogen or phosphorus atom; and X is a halogen atom or a C₁₋₈ alkoxy group or C₆₋₁₈ aryloxy group. Exemplary phase transfer catalysts include (CH₃(CH₂)₃)₄N⁺X⁻, (CH₃(CH₂)₃)₄P⁺X⁻, (CH₃(CH₂)₅)₄N⁺X⁻, (CH₃(CH₂)₆)₄N⁺X⁻, (CH₃(CH₂)₄)₄N⁺X⁻, CH₃(CH₃(CH₂)₃)₃N⁺X⁻, and CH₃(CH₃(CH₂)₂)₃N⁺X⁻, wherein X is Cl⁻, Br⁻, a C₁₋₈ alkoxy group or a C₆₋₁₈ aryloxy group. An effective amount of a phase transfer catalyst can be 0.1 to 10 wt. %, or 0.5 to 2 wt. %, each based on the weight of bisphenol in the phosgenation mixture.

Alternatively, melt processes can be used to make the polycarbonates. Melt polymerization may be conducted as a batch process or as a continuous process. In either case, the melt polymerization conditions used may comprise two or more distinct reaction stages, for example, a first reaction stage in which the starting dihydroxy aromatic compound and diaryl carbonate are converted into an oligomeric polycarbonate and a second reaction stage wherein the oligomeric polycarbonate formed in the first reaction stage is converted to high molecular weight polycarbonate. Such “staged” polymerization reaction conditions are especially suitable for use in continuous polymerization systems wherein the starting monomers are oligomerized in a first reaction vessel and the oligomeric polycarbonate formed therein is continuously transferred to one or more downstream reactors in which the oligomeric polycarbonate is converted to high molecular weight polycarbonate. Typically, in the oligomerization stage the oligomeric polycarbonate produced has a number average molecular weight of about 1,000 to about 7,500 Daltons. In one or more subsequent polymerization stages the number average molecular weight (Mn) of the polycarbonate is increased to between about 8,000 and about 25,000 Daltons (using polycarbonate standard).

The term “melt polymerization conditions” is understood to mean those conditions necessary to effect reaction between a dihydroxy aromatic compound and a diaryl carbonate in the presence of a transesterification catalyst. Typically, solvents are not used in the process, and the reactants dihydroxy aromatic compound and the diaryl carbonate are in a molten state. The reaction temperature can be about 100° C. to about 350° C., specifically about 180° C. to about 310° C. The pressure may be at atmospheric pressure, supra-atmospheric pressure, or a range of pressures from atmospheric pressure to about 15 torr in the initial stages of the reaction, and at a reduced pressure at later stages, for example about 0.2 to about 15 torr. The reaction time is generally about 0.1 hours to about 10 hours.

The diaryl carbonate ester can be diphenyl carbonate, or an activated diphenyl carbonate having electron-withdrawing substituents on the aryl groups, such as bis(4-nitrophenyl)carbonate, bis(2-chlorophenyl)carbonate, bis(4-chlorophenyl)carbonate, bis(methyl salicyl)carbonate, bis(4-methylcarboxylphenyl) carbonate, bis(2-acetylphenyl) carboxylate, bis(4-acetylphenyl) carboxylate, or a combination comprising at least one of the foregoing.

Catalysts used in the melt polymerization of polycarbonates can include alpha or beta catalysts. Beta catalysts are typically volatile and degrade at elevated temperatures. Beta catalysts are therefore preferred for use at early low-temperature polymerization stages. Alpha catalysts are typically more thermally stable and less volatile than beta catalysts.

The alpha catalyst can comprise a source of alkali or alkaline earth ions. The sources of these ions include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide, as well as alkaline earth hydroxides such as magnesium hydroxide and calcium hydroxide. Other possible sources of alkali and alkaline earth metal ions include the corresponding salts of carboxylic acids (such as sodium acetate) and derivatives of ethylene diamine tetraacetic acid (EDTA) (such as EDTA tetrasodium salt, and EDTA magnesium disodium salt). Other alpha transesterification catalysts include alkali or alkaline earth metal salts of a non-volatile inorganic acid such as NaH₂PO₃, NaH₂PO₄, Na₂HPO₃, KH₂PO₄, CsH₂PO₄, Cs₂HPO₄, and the like, or mixed salts of phosphoric acid, such as NaKHPO₄, CsNaHPO₄, CsKHPO₄, and the like. Combinations comprising at least one of any of the foregoing catalysts can be used.

Possible beta catalysts can comprise a quaternary ammonium compound, a quaternary phosphonium compound, or a combination comprising at least one of the foregoing. The quaternary ammonium compound can be a compound of the structure (R⁴)₄N⁺X⁻, wherein each R⁴ is the same or different, and is a C₁₋₂₀ alkyl group, a C₄₋₂₀ cycloalkyl group, or a C₄₋₂₀ aryl group; and X⁻ is an organic or inorganic anion, for example a hydroxide, halide, carboxylate, sulfonate, sulfate, formate, carbonate, or bicarbonate. Examples of organic quaternary ammonium compounds include tetramethyl ammonium hydroxide, tetrabutyl ammonium hydroxide, tetramethyl ammonium acetate, tetramethyl ammonium formate, tetrabutyl ammonium acetate, and combinations comprising at least one of the foregoing. Tetramethyl ammonium hydroxide is often used. The quaternary phosphonium compound can be a compound of the structure (R⁵)₄P⁺X⁻, wherein each R⁵ is the same or different, and is a C₁₋₂₀ alkyl group, a C₄₋₂₀ cycloalkyl group, or a C₄₋₂₀ aryl group; and X⁻ is an organic or inorganic anion, for example a hydroxide, halide, carboxylate, sulfonate, sulfate, formate, carbonate, or bicarbonate. Where X⁻ is a polyvalent anion such as carbonate or sulfate it is understood that the positive and negative charges in the quaternary ammonium and phosphonium structures are properly balanced. For example, where R²⁰-R²³ are each methyl groups and X⁻ is carbonate, it is understood that X⁻ represents 2(CO₃ ⁻²). Examples of organic quaternary phosphonium compounds include tetramethyl phosphonium hydroxide, tetramethyl phosphonium acetate, tetramethyl phosphonium formate, tetrabutyl phosphonium hydroxide, tetrabutyl phosphonium acetate (TBPA), tetraphenyl phosphonium acetate, tetraphenyl phosphonium phenoxide, and combinations comprising at least one of the foregoing. TBPA is often used.

The amount of alpha and beta catalyst used can be based upon the total number of moles of dihydroxy compound used in the polymerization reaction. When referring to the ratio of beta catalyst, for example a phosphonium salt, to all dihydroxy compounds used in the polymerization reaction, it is convenient to refer to moles of phosphonium salt per mole of the dihydroxy compound, meaning the number of moles of phosphonium salt divided by the sum of the moles of each individual dihydroxy compound present in the reaction mixture. The alpha catalyst can be used in an amount sufficient to provide 1×10⁻² to 1×10⁻⁸ moles, specifically, 1×10⁻⁴ to 1×10⁻⁷ moles of metal per mole of the dihydroxy compounds used. The amount of beta catalyst (e.g., organic ammonium or phosphonium salts) can be 1×10⁻² to 1×10⁻⁵, specifically 1×10⁻³ to 1×10⁻⁴ moles per total mole of the dihydroxy compounds in the reaction mixture.

Branched polycarbonate blocks can be prepared by adding a branching agent during polymerization. These branching agents include polyfunctional organic compounds containing at least three functional groups selected from hydroxyl, carboxyl, carboxylic anhydride, haloformyl, and mixtures of the foregoing functional groups. Specific examples include trimellitic acid, trimellitic anhydride, trimellitic trichloride, tris-p-hydroxy phenyl ethane, isatin-bis-phenol, tris-phenol TC (1,3,5-tris((p-hydroxyphenyl)isopropyl)benzene), tris-phenol PA (4(4(1,1-bis(p-hydroxyphenyl)-ethyl) alpha, alpha-dimethyl benzyl)phenol), 4-chloroformyl phthalic anhydride, trimesic acid, and benzophenone tetracarboxylic acid. The branching agents can be added at a level of about 0.05 to about 5 wt. %. Combinations comprising linear polycarbonates and branched polycarbonates can be used.

All types of polycarbonate end groups are contemplated as being useful in the polycarbonate composition, provided that such end groups do not significantly adversely affect desired properties of the compositions. A chain stopper (also referred to as a capping agent) can be included during polymerization. The chain stopper limits molecular weight growth rate, and so controls molecular weight in the polycarbonate. Exemplary chain stoppers include certain mono-phenolic compounds, mono-carboxylic acid chlorides, and/or mono-chloroformates. Mono-phenolic chain stoppers are exemplified by monocyclic phenols such as phenol and C₁-C₂₂ alkyl-substituted phenols such as p-cumyl-phenol, resorcinol monobenzoate, and p- and tertiary-butyl phenol; and monoethers of diphenols, such as p-methoxyphenol. Alkyl-substituted phenols with branched chain alkyl substituents having 8 to 9 carbon atom can be specifically mentioned. Certain mono-phenolic UV absorbers can also be used as a capping agent, for example 4-substituted-2-hydroxybenzophenones and their derivatives, aryl salicylates, monoesters of diphenols such as resorcinol monobenzoate, 2-(2-hydroxyaryl)-benzotriazoles and their derivatives, 2-(2-hydroxyaryl)-1,3,5-triazines and their derivatives, and the like. Mono-carboxylic acid chlorides can also be used as chain stoppers. These include monocyclic, mono-carboxylic acid chlorides such as benzoyl chloride, C₁-C₂₂ alkyl-substituted benzoyl chloride, toluoyl chloride, halogen-substituted benzoyl chloride, bromobenzoyl chloride, cinnamoyl chloride, 4-nadimidobenzoyl chloride, and combinations thereof; polycyclic, mono-carboxylic acid chlorides such as trimellitic anhydride chloride, and naphthoyl chloride; and combinations of monocyclic and polycyclic mono-carboxylic acid chlorides. Chlorides of aliphatic monocarboxylic acids with less than or equal to about 22 carbon atoms are useful. Functionalized chlorides of aliphatic monocarboxylic acids, such as acryloyl chloride and methacryoyl chloride, are also useful. Also useful are mono-chloroformates including monocyclic, mono-chloroformates, such as phenyl chloroformate, alkyl-substituted phenyl chloroformate, p-cumyl phenyl chloroformate, toluene chloroformate, and combinations thereof.

In an embodiment, the polycarbonate is a branched polycarbonate comprising units as described above; greater than or equal to 3 mole %, based on the total moles of the polycarbonate, of moieties derived from a branching agent; and end-capping groups derived from an end-capping agent having a pKa between about 8.3 and about 11. The branching agent can comprise trimellitic trichloride, 1,1,1-tris(4-hydroxyphenyl)ethane or a combination of trimellitic trichloride and 1,1,1-tris(4-hydroxyphenyl)ethane, and the end-capping agent is phenol or a phenol containing a substituent of cyano group, aliphatic groups, olefinic groups, aromatic groups, halogens, ester groups, ether groups, or a combination comprising at least one of the foregoing. In a specific embodiment, the end-capping agent is phenol, p-t-butylphenol, p-methoxyphenol, p-cyanophenol, p-cumylphenol, or a combination comprising at least one of the foregoing.

The polycarbonate copolymers comprising carbonate units (1) and carbonate units (4) can have an intrinsic viscosity, as determined in chloroform at 25° C., of about 0.3 to about 1.5 deciliters per gram (dl/gm), specifically about 0.45 to about 1.0 dl/gm. The polycarbonate copolymers can have a weight average molecular weight of about 10,000 to about 200,000 g/mol, specifically about 20,000 to about 100,000 g/mol, as measured by gel permeation chromatography (GPC), using a crosslinked styrene-divinylbenzene column and calibrated to polycarbonate references. GPC samples are prepared at a concentration of about 1 mg per ml, and are eluted at a flow rate of about 1.5 ml per minute.

In another embodiment the polycarbonate polymer is a polycarbonate copolymer, in particular a poly(carbonate-arylate ester) containing the first repeating bisphenol carbonate units (1) and repeating arylate ester units of formula (7)

wherein Ar¹ is a C₆₋₃₂ hydrocarbyl group containing at least one aromatic group, e.g., a phenyl, naphthalene, anthracene, or the like. In an embodiment, Ar¹ is derived from an aromatic bisphenol as described above in connection with units (1) and (4), a monoaryl dihydroxy compound (6), or a combination comprising different bisphenol or monoaryl dihydroxy compounds. Thus, arylate ester units (7) can be derived by reaction of isophthalic acid, terephthalic acid, or a combination comprising at least one of the foregoing (referred to herein as a “phthalic acid”), with any of the aromatic bisphenols described above, a monoaryl dihydroxy compound (6), or a combination comprising at least one of the foregoing. The molar ratio of isophthalate to terephthalate can be 1:99 to 99:1, or 80:20 to 20:80, or 60:40 to 40:60.

The poly(carbonate-arylate ester) comprising first bisphenol carbonate units (1) and arylate ester units (7) can be alternating or block copolymers of formula (8)

wherein R¹ and Ar¹ are as defined in formulae (1) and (7), respectively.

In general, the copolymers are block copolymers containing carbonate blocks and ester blocks. The weight ratio of total ester units to total carbonate units in the copolymers can vary broadly, for example from 99:1 to 1:99, or from 95:5 to 5:95, specifically from 90:10 to 10:90, or more specifically from 90:10 to 50:50, depending on the desired properties of the polycarbonate composition. The molar ratio of isophthalate to terephthalate in the ester units of the copolymers can also vary broadly, for example from 0:100 to 100:0, or from 92:8 to 8:92, more specifically from 98:2 to 45:55, depending on the desired properties of the polycarbonate composition. For example, the weight ratio of total ester units to total carbonate can be 99:1 to 40:60, or 90:10 to 50:40, wherein the molar ratio of isophthalate to terephthalate is from 99:1 to 40:50, more specifically 98:2 to 45:55, depending on the desired properties of the polycarbonate composition.

Additional carbonate units derived from the dihydroxy compound used to form the arylate ester units (7) can also be present as described above, for example in amounts of less than 20 mole %, less than 10 mole %, or less than 5 mole %, based on the total moles of units in the polycarbonate copolymer. It is also possible to have additional arylate ester units present derived from reaction of the phthalic acid with the dihydroxy compound used to form the carbonate units, for example in amounts of less than 20 mole %, less than 10 mole %, less than 5 mole %, or less than 1 mole % based on the total moles of units in the copolymer. In an embodiment, the combination of such additional carbonate units and such additional arylate ester units are present in an amount of less than 20 mole %, less than 10 mole %, less than 5 mole %, or less than 1 mole % based on the total moles of units in the copolymer.

A specific poly(carbonate-arylate ester) is a poly(carbonate)-co-(bisphenol arylate ester) comprising carbonate units (1), specifically bisphenol carbonate units, even more specifically bisphenol A carbonate units and repeating bisphenol arylate ester units. Bisphenol arylate units comprise residues of phthalic acid and a bisphenol, for example a bisphenol (2). In an embodiment the bisphenol arylate ester units are of formula (7a)

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, C₁₋₁₂ alkenyl, C₃₋₈ cycloalkyl, or C₁₋₁₂ alkoxy, p and q are each independently 0 to 4, and X^(a) is a bridging group between the two arylene groups, and is a single bond, —O—, —S—, —S(O)—, —S(O)₂—, —C(O)—, a C₁₋₁₁ alkylidene of the formula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independently hydrogen or C₁₋₁₀ alkyl, or a group of the formula —C(═R^(e))— wherein R^(e) is a divalent C₁₋₁₀ hydrocarbon group. In an embodiment, p and q is each 0 or 1, and R^(a) and R^(b) are each a C₁₋₃ alkyl group, specifically methyl, disposed meta to the oxygen on each ring, and X^(a) is an alkylidene of the formula —C(R^(c))(R^(d))— wherein Re and R^(d) are each C₁₋₆ alkyl. The bisphenol can be bisphenol A, where p and q are both 0 and X^(a) is isopropylidene.

In a specific embodiment, the polycarbonate copolymer is a poly(bisphenol A carbonate)-co-(bisphenol A-phthalate-ester) of formula (8a)

wherein y and x represent the weight percent of arylate-bisphenol A ester units and bisphenol A carbonate units, respectively. Generally, the units are present as blocks. In an embodiment, the weight percent of ester units y to carbonate units x in the copolymers is 50:50 to 99:1, or 55:45 to 90:10, or 75:25 to 95:5. Copolymers of formula (8a) comprising 35 to 45 wt. % of carbonate units and 55 to 65 wt. % of ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate of 45:55 to 55:45 are often referred to as poly(carbonate-ester)s (PCE), and copolymers comprising 15 to 25 wt. % of carbonate units and 75 to 85 wt. % of ester units having a molar ratio of isophthalate to terephthalate from 98:2 to 88:12 are often referred to as poly(phthalate-carbonate)s (PPC).

In another embodiment, a specific polycarbonate copolymer is a poly(carbonate)-co-(monoaryl arylate ester) containing carbonate units (1) and repeating monoaryl arylate ester units of formula (7b)

wherein each R^(h) is independently a halogen atom, a C₁₋₁₀ hydrocarbyl such as a C₁₋₁₀ alkyl group, a halogen-substituted C₁₋₁₀ alkyl group, a C₆₋₁₀ aryl group, or a halogen-substituted C₆₋₁₀ aryl group, and n is 0 to 4. Specifically, each R^(h) is independently a C₁₋₄ alkyl, and n is 0 to 3, 0 to 1, or 0. These poly(carbonate)-co-(monoaryl arylate ester) copolymers are of formula (8b)

wherein R¹ is as defined in formula (1) and R^(h), and n are as defined in formula (7b), and the mole ratio of x:m is 99:1 to 1:99, specifically 80:20 to 20:80, or 60:40 to 40:60.

Specifically, the monoaryl-arylate ester unit (7b) is derived from the reaction of a combination of isophthalic and terephthalic diacids (or derivatives thereof) with resorcinol (or reactive derivatives thereof) to provide isophthalate-terephthalate-resorcinol (“ITR” ester units) of formula (7c)

wherein m is 4 to 100, 4 to 90, 5 to 70, more specifically 5 to 50, or still more specifically 10 to 30. In an embodiment, the ITR ester units are present in the polycarbonate copolymer in an amount greater than or equal to 95 mol %, specifically greater than or equal to 99 mol %, and still more specifically greater than or equal to 99.5 mol % based on the total moles of ester units in the copolymer. Such (isophthalate-terephthalate-resorcinol)-carbonate copolymers (“ITR-PC”) can possess many desired features, including toughness, transparency, and weatherability. ITR-PC copolymers can also have desirable thermal flow properties. In addition, ITR-PC copolymers can be readily manufactured on a commercial scale using interfacial polymerization techniques, which allow synthetic flexibility and composition specificity in the synthesis of the ITR-PC copolymers.

A specific example of a poly(carbonate)-co-(monoaryl arylate ester) is a poly(bisphenol A carbonate)-co-(isophthalate-terephthalate-resorcinol ester) of formula (8c)

wherein m is 4 to 100, 4 to 90, 5 to 70, more specifically 5 to 50, or still more specifically 10 to 30, and the mole ratio of x:n is 99:1 to 1:99, specifically 90:10 to 10:90. The ITR ester units are present in the poly(carbonate-arylate ester) copolymer in an amount greater than or equal to 95 mol %, specifically greater than or equal to 99 mol %, and still more specifically greater than or equal to 99.5 mol % based on the total moles of ester units. Other carbonate units, other ester units, or a combination comprising at least one of the foregoing can be present, in a total amount of 1 to 20 mole % based on the total moles of units in the copolymers, for example resorcinol carbonate units of formula (20) and bisphenol ester units of formula (7a):

wherein, in the foregoing formulae, R^(h) is each independently a C₁₋₁₀ hydrocarbon group, n is 0 to 4, R^(a) and R^(h) are each independently a C₁₋₁₂ alkyl, p and q are each independently integers of 0 to 4, and x^(a) is a single bond, —O—, —S—, —S(O)—, —S(O)₂—, —C(O)—, or a C₁₋₁₃ alkylidene of formula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independently hydrogen or C₁₋₁₂ alkyl, or a group of the formula —C(═R^(e))— wherein R^(e) is a divalent C₁₋₁₂ hydrocarbon group. The bisphenol ester units can be bisphenol A phthalate ester units of the formula

In an embodiment, poly(bisphenol A carbonate)-co-(isophthalate-terephthalate-resorcinol ester) (8c) comprises 1 to 20 mol % of bisphenol A carbonate units, 20-98 mol % of isophthalic acid-terephthalic acid-resorcinol ester units, and optionally 1 to 60 mol % of resorcinol carbonate units, isophthalic acid-terephthalic acid-bisphenol A phthalate ester units, or a combination comprising at least one of the foregoing.

The polycarbonate copolymers comprising arylate ester units are generally prepared from polyester blocks. The polyester blocks can also be prepared by interfacial polymerization. Rather than utilizing the dicarboxylic acid or diol per se, the reactive derivatives of the acid or diol, such as the corresponding acid halides, in particular the acid dichlorides and the acid dibromides can be used. Thus, for example instead of using isophthalic acid, terephthalic acid, or a combination comprising at least one of the foregoing acids, isophthaloyl dichloride, terephthaloyl dichloride, or a combination comprising at least one of the foregoing dichlorides can be used. The polyesters can also be obtained by melt-process condensation as described above, by solution phase condensation, or by transesterification polymerization wherein, for example, a dialkyl ester such as dimethyl terephthalate can be transesterified with the dihydroxy reactant using acid catalysis, to generate the polyester blocks. Branched polyester blocks, in which a branching agent, for example, a glycol having three or more hydroxyl groups or a trifunctional or multifunctional carboxylic acid has been incorporated, can be used. Furthermore, it can be desirable to have various concentrations of acid and hydroxyl end groups on the polyester blocks, depending on the ultimate end use of the composition.

The polycarbonate copolymers comprising arylate ester units can have an M_(w) of 2,000 to 100,000 g/mol, specifically 3,000 to 75,000 g/mol, more specifically 4,000 to 50,000 g/mol, more specifically 5,000 to 35,000 g/mol, and still more specifically 17,000 to 30,000 g/mol. Molecular weight determinations are performed using GPC using a cross linked styrene-divinyl benzene column, at a sample concentration of 1 milligram per milliliter, and as calibrated with polycarbonate standards. Samples are eluted at a flow rate of about 1.0 ml/min with methylene chloride as the eluent.

In still another embodiment, the composition for manufacture of the train components can comprise a combination of a bisphenol A polycarbonate and a poly(bisphenol arylate ester) instead of, or in addition to, the above-described polycarbonate copolymers. The bisphenol A polycarbonate can be branched, or manufactured to contain end groups as described above, and can have an M_(w) of 2,000 to 100,000 g/mol, specifically 3,000 to 75,000 g/mol. Molecular weight determinations are performed using GPC using a cross linked styrene-divinyl benzene column, at a sample concentration of 1 milligram per milliliter, and as calibrated with polycarbonate standards. Samples are eluted at a flow rate of about 1.0 ml/min with methylene chloride as the eluent.

The poly(bisphenol arylate) is of formula (21)

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, C₁₋₁₂ alkenyl, C₃₋₈ cycloalkyl, or C₁₋₁₂ alkoxy, p and q are each independently 0 to 4, and x^(a) is a bridging group between the two arylene groups, and is a single bond, —O—, —S—, —S(O)—, —S(O)₂—, —C(O)—, a C₁₋₁₁ alkylidene of the formula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independently hydrogen or C₁₋₁₀ alkyl, or a group of the formula —C(═R^(e))— wherein R^(e) is a divalent C₁₋₁₀ hydrocarbon group. In an embodiment, p and q z are each 0, and x^(a) is a bridging group between the two arylene groups, and is a single bond, —O—, —S—, —S(O)—, —S(O)₂—, —C(O)—, a C₁₋₁₁ alkylidene of the formula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independently hydrogen or C₁₋₁₀ alkyl. Specifically, p and q are each 0 and x^(a) is isopropylidene, to provide a poly(bisphenol A-arylate).

The relative ratios of the bisphenol A polycarbonate and the poly(bisphenol arylate) can be varied to provide the desired properties, for example from (i) 5 to 50 wt. %, or 35 to 45 wt. % of a bisphenol A polycarbonate and (ii) 50 to 95 wt. %, specifically 55 to 65 wt. % of a poly(bisphenol A arylate), specifically a poly(bisphenol A arylate), based on the weight of the combination.

The polydialkylsiloxanes are silicone oils of low volatility, for example silicone oils with a viscosity of from 10 millipascal-second (mPa-s, also known as centipoise, cps) to 100,000,000 mPa-s at 25° C. are preferable, and silicone oils with a viscosity of from 20 mPa-s to 10,000,000 mPa-s at 25° C. Examples of such silicone oils include oils having linear, partially branched linear, cyclic, or branched molecular structures, with oils having linear or cyclic structures being specifically mentioned. The silicone oils have no, or substantially no reactive groups, for example no alkenyl groups, no silicon-bonded hydrogen atoms, no silanol groups, and no silicon-bonded hydrolyzable groups. The alkyl groups can be the same or different and can have 1 to 10 carbon atoms, 1 to 6 carbon atoms, or 1 to 3 carbon atoms. In an embodiment, the silicone oil is a polydimethylsiloxane, for example a polydimethylsiloxane having a viscosity from 50 to 1,000 mPa-s at 25° C.

The poly(carbonate-siloxane) copolymers, also referred to as “PC-siloxane,” can contain bisphenol carbonate units (1) and repeating siloxane units (also known as “diorganosiloxane units”). The siloxane units can be polysiloxane units of formula (9)

wherein each R is independently a C₁₋₁₃ monovalent hydrocarbyl group. For example, each R can independently be a C₁₋₁₃ alkyl group, C₁₋₁₃ alkoxy group, C₂₋₁₃ alkenyl group, C₂₋₁₃ alkenyloxy group, C₃₋₆ cycloalkyl group, C₃₋₆ cycloalkoxy group, C₆₋₁₄ aryl group, C₆₋₁₀ aryloxy group, C₇₋₁₃ arylalkyl group, C₇₋₁₃ arylalkoxy group, C₇₋₁₃ alkylaryl group, or C₇₋₁₃ alkylaryloxy group. The foregoing groups can be fully or partially halogenated with fluorine, chlorine, bromine, or iodine, or a combination comprising at least one of the foregoing. In an embodiment no halogens are present. Combinations of the foregoing R groups can be used in the same copolymer. In an embodiment, the polysiloxane comprises R groups that have minimal hydrocarbon content. In a specific embodiment, an R group with a minimal hydrocarbon content is a methyl group.

The average value of E in formula (9) can vary widely depending on the type and relative amount of each component in the polycarbonate composition, whether the polymer is linear, branched or a graft copolymer, the desired properties of the composition, and like considerations. In an embodiment, E has an average value of 2 to 500, 2 to 200, or 5 to 120, 10 to 100, 10 to 80, 2 to 30, or 30 to 80. In an embodiment E has an average value of 16 to 50, more specifically 20 to 45, and even more specifically 25 to 45. In another embodiment, E has an average value of 4 to 50, 4 to 15, specifically 5 to 15, more specifically 6 to 15, and still more specifically 7 to 10. In an embodiment, the polysiloxane units are structural units of formula (9a)

wherein E is as defined above; each R can independently be the same or different, and is as defined above; and each Ar can independently be the same or different, and is a substituted or unsubstituted C₆₋₃₀ compound containing an aromatic group, wherein the bonds are directly connected to the aromatic moiety. The Ar groups in formula (9a) can be derived from a C₆₋₃₀ dihydroxy aromatic compound, for example a bisphenol compound as described above or a monoaryl dihydroxy compound (6) above. Combinations comprising at least one of the foregoing dihydroxy aromatic compounds can also be used. Exemplary dihydroxy aromatic compounds are resorcinol (i.e., 1,3-dihydroxybenzene), 4-methyl-1,3-dihydroxybenzene, 5-methyl-1,3-dihydroxybenzene, 4,6-dimethyl-1,3-dihydroxybenzene, 1,4-dihydroxybenzene, 1,1-bis(4-hydroxyphenyl) methane, 1,1-bis(4-hydroxyphenyl) ethane, 2,2-bis(4-hydroxyphenyl) propane, 2,2-bis(4-hydroxyphenyl) butane, 2,2-bis(4-hydroxyphenyl) octane, 1,1-bis(4-hydroxyphenyl) propane, 1,1-bis(4-hydroxyphenyl) n-butane, 2,2-bis(4-hydroxy-1-methylphenyl) propane, 1,1-bis(4-hydroxyphenyl)cyclohexane, bis(4-hydroxyphenyl sulfide), and 1,1-bis(4-hydroxy-t-butylphenyl) propane. Combinations comprising at least one of the foregoing dihydroxy compounds can also be used. In an embodiment, the dihydroxy aromatic compound is unsubstituted, or is does not contain non-aromatic hydrocarbyl substituents such as alkyl, alkoxy, or alkylene substituents.

In a specific embodiment, where Ar is derived from resorcinol, the polysiloxane units are of the formula (9a-1)

or, where Ar is derived from bisphenol A, the polysiloxane has the formula (9a-2)

or a combination comprising at least one of the foregoing can be used, wherein E has an average value as described above, specifically an average value of 2 to 200.

In another embodiment, polydiorganosiloxane units are units of formula (9b)

wherein R and E are as described for formula (9), and each R² is independently a divalent C₁₋₃₀ alkylene or C₇₋₃₀ arylene-alkylene. In a specific embodiment, where R² is C₇₋₃₀ arylene-alkylene, the polydiorganosiloxane units are of formula (9b-1)

wherein R and E are as defined for formula (9), and each R³ is independently a divalent C₂₋₈ aliphatic group. Each M in formula (25) can be the same or different, and can be a halogen, cyano, nitro, C₁₋₈ alkylthio, C₁₋₈ alkyl, C₁₋₈ alkoxy, C₂₋₈ alkenyl, C₂₋₈ alkenyloxy group, C₃₋₈ cycloalkyl, C₃₋₈ cycloalkoxy, C₆₋₁₀ aryl, C₆₋₁₀ aryloxy, C₇₋₁₂ arylalkyl, C₇₋₁₂ arylalkoxy, C₇₋₁₂ alkylaryl, or C₇₋₁₂ alkylaryloxy, wherein each n is independently 0, 1, 2, 3, or 4. In an embodiment, M is bromo or chloro, an alkyl group such as methyl, ethyl, or propyl, an alkoxy group such as methoxy, ethoxy, or propoxy, or an aryl group such as phenyl, chlorophenyl, or tolyl; R³ is a dimethylene, trimethylene or tetramethylene group; and R is a C₁₋₈ alkyl, haloalkyl such as trifluoropropyl, cyanoalkyl, or aryl such as phenyl, chlorophenyl or tolyl. In another embodiment, R is methyl, or a combination of methyl and trifluoropropyl, or a combination of methyl and phenyl. In still another embodiment, M is methoxy, n is 0 or 1, R³ is a divalent C₁₋₃ aliphatic group, and R is methyl. The foregoing poly(carbonate-siloxane) copolymers can be manufactured by the methods described in U.S. Pat. No. 6,072,011 to Hoover, for example.

In a specific embodiment, the polysiloxane units are eugenol-capped polysiloxane units of formula (9b-2)

where E has an average value as described above, specifically 2 to 200, 2 to 100, 2 to 90, 2 to 80, or 2 to 30, 20 to 20, or 30 to 80. In another specific embodiment, the polysiloxane units are of formula (9b-3) or (9b-4)

where E has an average value as defined above, specifically an average value of 2 to 200, 2 to 100, 2 to 90, 2 to 80, or 2 to 30, 20 to 20, or 30 to 80.

The relative amount of carbonate units (1) and polysiloxane units (9) in the PC-siloxane copolymers depends on the desired properties of the polycarbonate composition, such as impact, smoke density, heat release, and melt viscosity. In particular the polycarbonate copolymer is selected to have an average value of E that provides good impact and/or transparency properties, as well as to provide the desired weight percent of siloxane units in the polycarbonate composition. For example, the polycarbonate copolymers can comprise siloxane units in an amount of 0.1 to 60 weight percent (wt. %), specifically 0.5 to 55 wt. %, or 0.5 to 45 wt. %, based on the total weight of the polymers in the polycarbonate composition, with the proviso that the siloxane units are provided by polysiloxane units covalently bonded in the polymer backbone of the polycarbonate copolymer.

A specific PC-siloxane comprises carbonate units (1) derived from bisphenol A, and second repeating siloxane units (9b-2), (9b-3), (9b-4), or a combination comprising at least one of the foregoing, specifically (9b-2). This polycarbonate copolymer can comprise the siloxane units in an amount of 0.1 to 60 weight percent (wt. %), 0.5 to 55 wt. %, 0.5 to 45 wt. % 0.5 to 30 wt. %, or 0.5 to 20 wt. %, based on the total weight of the polycarbonate copolymer, with the proviso that the siloxane units are covalently bound to the polymer backbone of the polycarbonate copolymer. In an embodiment, the remaining units are bisphenol units (1). Transparency can be achieved in this embodiment when E has an average value of 4 to 50, 4 to 15, specifically 5 to 15, more specifically 6 to 15, and still more specifically 7 to 10. The transparent PC-siloxanes can be manufactured using one or both of the tube reactor processes described in U.S. Patent Application No. 2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 may be used to synthesize the poly(siloxane-carbonate) copolymers.

These and other methods for the manufacture of the PC-siloxane copolymers are known. The PC-siloxane copolymers can have an intrinsic viscosity, as determined in chloroform at 25° C., of 0.3 to 1.5 deciliters per gram (dl/g), specifically 0.45 to 1.0 dl/g. The PC-siloxane copolymers can have a weight average molecular weight (M_(w)) of 10,000 to 100,000 g/mol, as measured by gel permeation chromatography (GPC) using a cross linked styrene-divinyl benzene column, at a sample concentration of 1 milligram per milliliter, and as calibrated with polycarbonate standards.

The addition of relatively small amount of PC-siloxane to the above described polycarbonate polymers reduces the smoke density DS-4 values significantly. Similar improvements in DS-4 values can be achieved at the same silicon content irrespective of the architecture of the PC-siloxane. Further, the length of the siloxane block does not have a significant influence on the smoke density when compared at the same silicon content in the polycarbonate composition. In an embodiment, the PC-siloxane is present in an amount effective to provide 0.1 to 1.00 wt. % of silicon based on the total weight of the composition.

In an embodiment, the low smoke polycarbonate compositions do not contain or substantially free of any brominated polycarbonate. As used herein, “substantially free of” refers to a composition containing less than 5 wt. %, specifically less than 1 wt. %, more specifically less than 0.1 wt. % of a brominated polycarbonate.

The polycarbonate compositions can include various other polymers to adjust the properties of the polycarbonate compositions, with the proviso that the other polymers are selected so as to not adversely affect the desired properties of the polycarbonate composition significantly, in particular low smoke density and low heat release. For example, combination of a polycarbonate copolymer as described above and a homopolycarbonate having repeating units (1) such as a bisphenol A homopolycarbonate can still provide polycarbonate compositions having the required low smoke density. Other polymers include an impact modifier such as natural rubber, fluoroelastomers, ethylene-propylene rubber (EPR), ethylene-butene rubber, ethylene-propylene-diene monomer rubber (EPDM), acrylate rubbers, hydrogenated nitrile rubber (HNBR) silicone elastomers, and elastomer-modified graft copolymers such as styrene-butadiene-styrene (SBS), styrene-butadiene rubber (SBR), styrene-ethylene-butadiene-styrene (SEBS), acrylonitrile-butadiene-styrene (ABS), acrylonitrile-ethylene-propylene-diene-styrene (AES), styrene-isoprene-styrene (SIS), methyl methacrylate-butadiene-styrene (MBS), high rubber graft (HRG), and the like can be present. In general such other polymers provide less than 50 wt. %, less than 40 wt. %, less than 30 wt. %, less than 20 wt. %, or less than 10 wt. % of the total composition. In an embodiment, no other polymers are present. In a specific embodiment, no polymers containing halogen are present in the polycarbonate compositions.

The polycarbonate compositions can include various additives ordinarily incorporated into flame retardant compositions having low smoke density and low heat release, with the proviso that the additive(s) are selected so as to not adversely affect the desired properties of the polycarbonate composition significantly, in particular low smoke density and low heat release. Such additives can be mixed at a suitable time during the mixing of the components for forming the composition. Exemplary additives include fillers, reinforcing agents, antioxidants, heat stabilizers, light stabilizers, ultraviolet (UV) light stabilizers, plasticizers, lubricants, mold release agents, antistatic agents, colorants such as such as titanium dioxide, carbon black, and organic dyes, surface effect additives, light diffuser additives, radiation stabilizers, additional flame retardants, and anti-drip agents. A combination of additives can be used. In general, the additives are used in the amounts generally known to be effective. The total amount of additives (other than any filler or reinforcing agents) is generally 0.01 to 25 parts per hundred parts by the total weight of the polymers in the composition (PHR).

Examples of inorganic pigments are white pigments such as titanium dioxide in its three modifications of rutile, anatase or brookite, lead white, zinc white, zinc sulfide or lithopones; black pigments such as carbon black, black iron oxide, iron manganese black or spinel black; chromatic pigments such as chromium oxide, chromium oxide hydrate green, cobalt green or ultramarine green, cobalt blue, iron blue, Milori blue, ultramarine blue or manganese blue, ultramarine violet or cobalt and manganese violet, red iron oxide, cadmium sulfoselenide, molybdate red or ultramarine red; brown iron oxide, mixed brown, spinel phases and corundum phases or chromium orange; yellow iron oxide, nickel titanium yellow, chromium titanium yellow, cadmium sulfide, cadmium zinc sulfide, chromium yellow, zinc yellow, alkaline earth metal chromates, Naples yellow; bismuth vanadate, and effect pigments such as interference pigments and luster pigments. Other specific inorganic pigments include Pigment White 6, Pigment White 7, Pigment Black 7, Pigment Black 11, Pigment Black 22, Pigment Black 27/30, Pigment Yellow 34, Pigment Yellow 35/37, Pigment Yellow 42, Pigment Yellow 53, Pigment Brown 24, Pigment Yellow 119, Pigment Yellow 184, Pigment Orange 20, Pigment Orange 75, Pigment Brown 6, Pigment Brown 29, Pigment Brown 31, Pigment Yellow 164, Pigment Red 101, Pigment Red 104, Pigment Red 108, Pigment Red 265, Pigment Violet 15, Pigment Blue 28/36, Pigment Blue 29, Pigment Green 17, and Pigment Green 26/50. A combination comprising at least one of the foregoing pigments can be used.

Exemplary dyes are generally organic materials and include coumarin dyes such as coumarin 460 (blue), coumarin 6 (green), nile red or the like; lanthanide complexes; hydrocarbon and substituted hydrocarbon dyes; polycyclic aromatic hydrocarbon dyes; scintillation dyes such as oxazole or oxadiazole dyes; aryl- or heteroaryl-substituted poly (C₂₋₈) olefin dyes; carbocyanine dyes; indanthrone dyes; phthalocyanine dyes; oxazine dyes; carbostyryl dyes; napthalenetetracarboxylic acid dyes; porphyrin dyes; bis(styryl)biphenyl dyes; acridine dyes; anthraquinone dyes; cyanine dyes; methine dyes; arylmethane dyes; azo dyes; indigoid dyes, thioindigoid dyes, diazonium dyes; nitro dyes; quinone imine dyes; aminoketone dyes; tetrazolium dyes; thiazole dyes; perylene dyes, perinone dyes; bis-benzoxazolylthiophene (BBOT); triarylmethane dyes; xanthene dyes; thioxanthene dyes; naphthalimide dyes; lactone dyes; fluorophores such as anti-stokes shift dyes which absorb in the near infrared wavelength and emit in the visible wavelength, or the like; luminescent dyes such as 7-amino-4-methylcoumarin; 3-(2′-benzothiazolyl)-7-diethylaminocoumarin; 2-(4-biphenylyl)-5-(4-t-butylphenyl)-1,3,4-oxadiazole; 2,5-bis-(4-biphenylyl)-oxazole; 2,2′-dimethyl-p-quaterphenyl; 2,2-dimethyl-p-terphenyl; 3,5,3″″,5″″-tetra-t-butyl-p-quinquephenyl; 2,5-diphenylfuran; 2,5-diphenyloxazole; 4,4′-diphenylstilbene; 4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran; 1,1′-diethyl-2,2′-carbocyanine iodide; 3,3′-diethyl-4,4′,5,5′-dibenzothiatricarbocyanine iodide; 7-dimethylamino-1-methyl-4-methoxy-8-azaquinolone-2; 7-dimethylamino-4-methylquinolone-2; 2-(4-(4-dimethylaminophenyl)-1,3-butadienyl)-3-ethylbenzothiazolium perchlorate; 3-diethylamino-7-diethyliminophenoxazonium perchlorate; 2-(1-naphthyl)-5-phenyloxazole; 2,2′-p-phenylen-bis(5-phenyloxazole); rhodamine 700; rhodamine 800; pyrene, chrysene, rubrene, coronene, or the like; or combinations comprising at least one of the foregoing dyes. Dyes can be used in amounts of 0.001 to 5 PHR.

The use of pigments such as titanium dioxide produces white compositions, which are commercially desirable. It has surprisingly been found that the use of titanium dioxide can further improve smoke density and/or heat release properties. Pigments such as titanium dioxide (or other mineral fillers) can be present in the polycarbonate compositions in amounts of 0 to 12 wt. %, 0.1 to 12 wt. %, 0.1 to 9 wt. %, 0.5 to 5 wt. %, or 0.5 to 3 wt. %, each based on the total weight of the composition.

Compositions used to form light-diffusive articles, for example light-diffusive train components, can further comprise a light diffuser additive, i.e., a plurality of light-diffusive particles to provide the light-diffusive effect. Such particles are generally insoluble in the polymers of the thermoplastic compositions. Light-diffuser additives include silicone particles, e.g., polymethylsilsesquioxanes available from GE Silicones under the trade name Tospearl*, crosslinked poly(methyl methacrylate) (PMMA) and other organic polymer particles, e.g., methyl methacrylate/ethyleneglycol dimethacrylate copolymers available from Sekisui Plastics Co. under the trade name TECHPOLYMER MBS*, and low levels of TiO₂. A combination comprising at least one of the foregoing types of light diffuser additives can be used. Such diffuser particles can be added to high clarity or medium clarity compositions to provide light-diffusive compositions, for example in an amount of 0.05 to 10.0 wt. %, 0.2 to 8.0 wt. %, 0.5 to 6.0 wt. %, or 0.5 to 5.00 wt. % of the light diffuser additive, based on the total weight of the polymers in the in the thermoplastic compositions. In general, greater amounts of light diffuser additive is used in the manufacture of thinner articles to obtain the same degree of light diffusion. In an embodiment the light diffuser additives are silicone particles. The light diffuser additives can also be PMMA. Likewise, the light diffuser additives can be a combination of silicone particles and PMMA particles.

Exemplary antioxidant additives include organophosphites such as tris(nonyl phenyl)phosphite, tris(2,4-di-t-butylphenyl)phosphite, bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite, distearyl pentaerythritol diphosphite; alkylated monophenols or polyphenols; alkylated reaction products of polyphenols with dienes, such as tetrakis[methylene(3,5-di-tert-butyl-4-hydroxyhydrocinnamate)]methane; butylated reaction products of para-cresol or dicyclopentadiene; alkylated hydroquinones; hydroxylated thiodiphenyl ethers; alkylidene-bisphenols; benzyl compounds; esters of beta-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid with monohydric or polyhydric alcohols; esters of beta-(5-tert-butyl-4-hydroxy-3-methylphenyl)-propionic acid with monohydric or polyhydric alcohols; esters of thioalkyl or thioaryl compounds such as distearylthiopropionate, dilaurylthiopropionate, ditridecylthiodipropionate, octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, pentaerythrityl-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; amides of beta-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid, or combinations comprising at least one of the foregoing antioxidants. Antioxidants are used in amounts of 0.01 to 0.1 PHR.

Exemplary heat stabilizer additives include organophosphites such as triphenyl phosphite, tris-(2,6-dimethylphenyl)phosphite, and tris-(mixed mono- and di-nonylphenyl)phosphite; phosphonates such as dimethylbenzene phosphonate, phosphates such as trimethyl phosphate; or combinations comprising at least one of the foregoing heat stabilizers. Heat stabilizers are used in amounts of 0.01 to 0.1 PHR.

Light stabilizers and/or ultraviolet light (UV) absorbing additives can also be used. Exemplary light stabilizer additives include benzotriazoles such as 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-octylphenyl)-benzotriazole and 2-hydroxy-4-n-octoxy benzophenone, or combinations comprising at least one of the foregoing light stabilizers. Light stabilizers are used in amounts of 0.01 to 5 PHR.

Exemplary UV absorbing additives include hydroxybenzophenones; hydroxybenzotriazoles; hydroxybenzotriazines; cyanoacrylates; oxanilides; benzoxazinones; 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)-phenol (CYASORB® 5411); 2-hydroxy-4-n-octyloxybenzophenone (CYASORB® 531); 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl]-5-(octyloxy)-phenol (CYASORB® 1164); 2,2′-(1,4-phenylene)bis(4H-3,1-benzoxazin-4-one) (CYASORB® UV-3638); 1,3-bis[(2-cyano-3,3-diphenylacryloyl)oxy]-2,2-bis[[(2-cyano-3,3-diphenylacryloyl)oxy]methyl]propane (UVINUL® 3030); 2,2′-(1,4-phenylene)bis(4H-3,1-benzoxazin-4-one); 1,3-bis[2-cyano-3,3-diphenylacryloyl)oxy]-2,2-bis[[(2-cyano-3,3-diphenylacryloyl)oxy]methyl]propane; nano-size inorganic materials such as titanium oxide, cerium oxide, and zinc oxide, all with particle size less than or equal to 100 nanometers; or combinations comprising at least one of the foregoing UV absorbers. UV absorbers are used in amounts of 0.01 to 5 PHR.

Plasticizers, lubricants, and/or mold release agents can also be used. There is considerable overlap among these types of materials, which include phthalic acid esters such as dioctyl-4,5-epoxy-hexahydrophthalate; tris-(octoxycarbonylethyl)isocyanurate; tristearin; poly-alpha-olefins; epoxidized soybean oil; silicones, including silicone oils; esters, for example, fatty acid esters such as alkyl stearyl esters, e.g., methyl stearate, stearyl stearate, pentaerythritol tetrastearate, and the like; combinations of methyl stearate and hydrophilic and hydrophobic nonionic surfactants comprising polyethylene glycol polymers, polypropylene glycol polymers, poly(ethylene glycol-co-propylene glycol) copolymers, or a combination comprising at least one of the foregoing glycol polymers, e.g., methyl stearate and polyethylene-polypropylene glycol copolymer in a solvent; waxes such as beeswax, montan wax, and paraffin wax. Such materials are used in amounts of 0.1 to 1 PHR.

Flame retardant salts are not needed to obtain the desired low smoke and low heat release properties. Examples of flame retardant salts include of C₁₋₁₆ alkyl sulfonate salts such as potassium perfluorobutane sulfonate (Rimar salt), potassium perfluorooctane sulfonate, tetraethylammonium perfluorohexane sulfonate, and potassium diphenylsulfone sulfonate (KSS); salts such as Na₂CO₃, K₂CO₃, MgCO₃, CaCO₃, and BaCO₃, phosphate salts, or fluoro-anion complexes such as Li₃AlF₆, BaSiF₆, KBF₄, K₃AlF₆, KAlF₄, K₂SiF₆, and/or Na₃AlF₆. In an embodiment, no flame retardant salts are present. When present, flame retardant salts are present in amounts of 0.01 to 10 PHR, more specifically 0.02 to 1 PHR.

Organic flame retardants can be present, for example organic compounds that include phosphorus, nitrogen, bromine, and/or chlorine. However, halogenated flame retardants are generally avoided, such that the polycarbonate composition can be essentially free of chlorine and bromine “Essentially free of chlorine and bromine” as used herein means having a bromine and/or chlorine content of less than or equal to 100 parts per million by weight (ppm), less than or equal to 75 ppm, or less than or equal to 50 ppm, based on the total parts by weight of the composition, excluding any filler.

The polycarbonate compositions further comprise an organophosphorus flame retardant in an amount effective to provide 0.1 to 2.0 wt. % phosphorus, based on the weight of the composition. For example, the organophosphorus compound, specifically BPADP or RDP can be present in an amount of 2 to 20 wt. %, which is effective to provide 0.1 to 2.0 wt. % of phosphorus based on the total weight of the composition. Inventors have found that the presence of certain organophosphorus flame retardants for example BPADP, has a positive effect on the smoke density as it further reduced DS-values of a composition containing a polycarbonate polymer and a second polymer, but not the flame retardant. Further, it was found that these flame retardants have a positive effect on MAHRE, as they reduce MAHRE of a composition containing a polycarbonate polymer and a second polymer but not the organophosphorus component. Further, certain organophosphorus flame retardants improve the melt flow while at the same time maintain ductility even at relatively high loading levels.

Organophosphorus compounds include aromatic organophosphorus compounds having at least one organic aromatic group and at least one phosphorus-containing group, as well as organic compounds having at least one phosphorus-nitrogen bond.

In the aromatic organophosphorus compounds that have at least one organic aromatic group, the aromatic group can be a substituted or unsubstituted C₃₋₃₀ group containing one or more of a monocyclic or polycyclic aromatic moiety (which can optionally contain with up to three heteroatoms (N, O, P, S, or Si)) and optionally further containing one or more nonaromatic moieties, for example alkyl, alkenyl, alkynyl, or cycloalkyl. The aromatic moiety of the aromatic group can be directly bonded to the phosphorus-containing group, or bonded via another moiety, for example an alkylene group. The aromatic moiety of the aromatic group can be directly bonded to the phosphorus-containing group, or bonded via another moiety, for example an alkylene group. In an embodiment the aromatic group is the same as an aromatic group of the polycarbonate backbone, such as a bisphenol group (e.g., bisphenol A), a monoarylene group (e.g., a 1,3-phenylene or a 1,4-phenylene), or a combination comprising at least one of the foregoing.

The phosphorus-containing group can be a phosphate (P(═O)(OR)₃), phosphite (P(OR)₃), phosphonate (RP(═O)(OR)₂), phosphinate (R₂P(═O)(OR)), phosphine oxide (R₃P(═O)), or phosphine (R₃P), wherein each R in the foregoing phosphorus-containing groups can be the same or different, provided that at least one R is an aromatic group. A combination of different phosphorus-containing groups can be used. The aromatic group can be directly or indirectly bonded to the phosphorus, or to an oxygen of the phosphorus-containing group (i.e., an ester).

In an embodiment the aromatic organophosphorus compound is a monomeric phosphate. Representative monomeric aromatic phosphates are of the formula (GO)₃P═O, wherein each G is independently an alkyl, cycloalkyl, aryl, alkylarylene, or arylalkylene group having up to 30 carbon atoms, provided that at least one G is an aromatic group. Two of the G groups can be joined together to provide a cyclic group. In some embodiments G corresponds to a monomer used to form the polycarbonate, e.g., resorcinol. Exemplary phosphates include phenyl bis(dodecyl)phosphate, phenyl bis(neopentyl)phosphate, phenyl bis(3,5,5′-trimethylhexyl)phosphate, ethyl diphenyl phosphate, 2-ethylhexyl di(p-tolyl)phosphate, bis(2-ethylhexyl) p-tolyl phosphate, tritolyl phosphate, bis(2-ethylhexyl) phenyl phosphate, tri(nonylphenyl)phosphate, bis(dodecyl) p-tolyl phosphate, dibutyl phenyl phosphate, 2-chloroethyl diphenyl phosphate, p-tolyl bis(2,5,5′-trimethylhexyl)phosphate, 2-ethylhexyl diphenyl phosphate, and the like. A specific aromatic phosphate is one in which each G is aromatic, for example, triphenyl phosphate, tricresyl phosphate, isopropylated triphenyl phosphate, and the like.

Di- or polyfunctional aromatic phosphorus-containing compounds are also useful, for example, compounds of formula (14)

wherein each G² is independently a hydrocarbon or hydrocarbonoxy having 1 to 30 carbon atoms. In some embodiments G corresponds to a monomer used to form the polycarbonate, e.g., resorcinol.

Specific aromatic organophosphorus compounds have two or more phosphorus-containing groups, and are inclusive of acid esters of formula (15)

wherein R¹⁶, R¹⁷, R¹⁸, and R¹⁹ are each independently C₁₋₈ alkyl, C₅₋₆ cycloalkyl, C₆₋₂₀ aryl, or C₇₋₁₂ arylalkylene, each optionally substituted by C₁₋₁₂ alkyl, specifically by C₁₋₄ alkyl and X is a mono- or poly-nuclear aromatic C₆₋₃₀ moiety or a linear or branched C₂₋₃₀ aliphatic radical, which can be OH-substituted and can contain up to 8 ether bonds, provided that at least one of R¹⁶, R¹⁷, R¹⁸, R¹⁹, and X is an aromatic group. In some embodiments R¹⁶, R¹⁷, R¹⁸, and R¹⁹ are each independently C₁₋₄ alkyl, naphthyl, phenyl(C₁₋₄)alkylene, or aryl groups optionally substituted by C₁₋₄ alkyl. Specific aryl moieties are cresyl, phenyl, xylenyl, propylphenyl, or butylphenyl. In some embodiments X in formula (15) is a mono- or poly-nuclear aromatic C₆₋₃₀ moiety derived from a diphenol. Further in formula (15), n is each independently 0 or 1; in some embodiments n is equal to 1. Also in formula (15), q is from 0.5 to 30, from 0.8 to 15, from 1 to 5, or from 1 to 2. Specifically, X can be represented by the following divalent groups (16), or a combination comprising one or more of these divalent groups.

In these embodiments, each of R¹⁶, R¹⁷, R¹⁸, and R¹⁹ can be aromatic, i.e., phenyl, n is 1, and p is 1-5, specifically 1-2. In some embodiments at least one of R¹⁶, R¹⁷, R¹⁸, R¹⁹, and X corresponds to a monomer used to form the polycarbonate, e.g., bisphenol A or resorcinol. In another embodiment, X is derived especially from resorcinol, hydroquinone, bisphenol A, or diphenylphenol, and R¹⁶, R¹⁷, R¹⁸, R¹⁹, is aromatic, specifically phenyl. A specific aromatic organophosphorus compound of this type is resorcinol bis(diphenyl phosphate), also known as RDP. Another specific class of aromatic organophosphorus compounds having two or more phosphorus-containing groups are compounds of formula (17)

wherein R¹⁶, R¹⁷, R¹⁸, R¹⁹, n, and q are as defined for formula (19) and wherein Z is C₁₋₇ alkylidene, C₁₋₇ alkylene, C₅₋₁₂ cycloalkylidene, —O—, —S—, —SO₂—, or —CO—, specifically isopropylidene. A specific aromatic organophosphorus compound of this type is bisphenol A bis(diphenyl phosphate), also known as BPADP, wherein R¹⁶, R¹⁷, R¹⁸, and R¹⁹ are each phenyl, each n is 1, and q is from 1 to 5, from 1 to 2, or 1.

Organophosphorus compounds containing at least one phosphorus-nitrogen bond includes phosphazenes, phosphorus ester amides, phosphoric acid amides, phosphonic acid amides, phosphinic acid amides, and tris(aziridinyl)phosphine oxide. Phosphazenes (18) and cyclic phosphazenes (19)

in particular can used, wherein w1 is 3 to 10,000 and w2 is 3 to 25, specifically 3 to 7, and each R^(w) is independently a C₁₋₁₂ alkyl, alkenyl, alkoxy, aryl, aryloxy, or polyoxyalkylene group. In the foregoing groups at least one hydrogen atom of these groups can be substituted with a group having an N, S, O, or F atom, or an amino group. For example, each R^(w) can be a substituted or unsubstituted phenoxy, an amino, or a polyoxyalkylene group. Any given R^(w) can further be a crosslink to another phosphazene group. Exemplary crosslinks include bisphenol groups, for example bisphenol A groups. Examples include phenoxy cyclotriphosphazene, octaphenoxy cyclotetraphosphazene decaphenoxy cyclopentaphosphazene, and the like. A combination of different phosphazenes can be used. A number of phosphazenes and their synthesis are described in H. R. Allcook, “Phosphorus-Nitrogen Compounds” Academic Press (1972), and J. E. Mark et al., “Inorganic Polymers” Prentice-Hall International, Inc. (1992).

Accordingly, depending on the particular organophosphorus compound used, the polycarbonate compositions can comprise from 0.3 to 20 wt. %, or 0.5 to 15 wt. %, or 3.5 to 12 wt. % of the organophosphorus flame retardant, each based on the total weight of the composition. Specifically, the organophosphorus compounds can be bisphenol A bis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate), tricresyl phosphate, or a combination comprising at least one of the foregoing.

Anti-drip agents in most embodiments are not used in the polycarbonate compositions. Anti-drip agents include a fibril-forming or non-fibril forming fluoropolymer such as polytetrafluoroethylene (PTFE). The anti-drip agent can be encapsulated by a rigid copolymer, for example styrene-acrylonitrile copolymer (SAN). PTFE encapsulated in SAN is known as TSAN. Antidrip agents are substantially absent or completely absent from the polycarbonate compositions in some embodiments.

Methods for forming the polycarbonate compositions can vary. In an embodiment, the polymers are combined (e.g., blended) with any additives (e.g., a mold release agent) such as in a screw-type extruder. The polymers any additives can be combined in any order, and in form, for example, powder, granular, filamentous, as a masterbatch, and the like. The polycarbonate compositions can be foamed, extruded into a sheet, or optionally pelletized. Methods of foaming a polycarbonate composition using frothing or physical or chemical blowing agents are known and can be used. The pellets can be used for molding into articles, foaming, or they can be used in forming a sheet of the flame retardant polycarbonate composition. In some embodiments, the composition can be extruded (or co-extruded with a coating or other layer) in the form of a sheet and/or can be processed through calendaring rolls to form the desired sheet.

As discussed above, the polycarbonate compositions are formulated to meet strict low smoke density requirements. The relative amounts of polycarbonate polymer and the second polymer in the polycarbonate compositions depends on the particular polycarbonate polymer and the second polymer used, the targeted level of smoke density and heat release, and other desired properties of the polycarbonate composition, such as transparency, haze, impact strength and flow. In an embodiment, the second polymer is present in an amount effective to provide 0.10 to 1.00 wt. % silicon based on the total weight of the composition, and within this range the specific amount is selected to be effective to provide a smoke density (Ds-4) of less than 300, or of less than 250, or of less than 200 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m². These values can be obtained in articles having a wide range of thicknesses, for example from 0.1 to 10 mm, or 0.5 to 5 mm.

The polycarbonate compositions can further have a maximum average rate of heat emission (MAHRE) of 90 kW/m² or less, or 80 kW/m² or less, or 70 kW/m² or less as measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m².

Use of a PC-siloxane, a polydialkylsiloxane, or a combination of a PC-siloxane and a polydialkylsiloxane and an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition can lower smoke density (Ds-4) of polycarbonate polymers to the desired levels. For example, polycarbonate polymers such as PPP-BP/BPA or PPC have limited inherent smoke and heat release properties, a combination of these polycarbonate polymers with a PC-siloxane such as (bisphenol A carbonate)-co-(polydimethylsiloxane) has positive effect on the smoke density (Ds-4) measured according to ISO5659-2 on a 3 mm thick plaque at 50 kW/m², such that these compositions are suitable for EN-45545 type applications (R6 applications qualifying for HL2 compliance, a smoke density (Ds-4) at or below 300 is required at 50 kW/m²), provided that the other required properties (e.g. heat release) meet the selection criteria as well.

Thus, in some embodiments the compositions can have a MAHRE of 90 kW/m² or less as measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², a Ds-4 smoke density of 300 or less as measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², measured according to resulting in R6 applications in compliance with Hazard Level 2 rating for the EN45545 (2013) standard. These values can be obtained in articles having a wide range of thicknesses, for example from 0.1 to 10 mm, or 0.5 to 5 mm.

The compositions can also have a critical heat flux at extinguishment (CFE) at or above 20 kW/m², at or above 22 kW/m², or at or above 24 kW/m² measured according to ISO 5658-2 on a 3 mm thick plaque.

Thus, in some embodiments the compositions can have a MAHRE of 90 kW/m² or less as measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², a Ds-4 smoke density of 300 or less as measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², and a critical heat flux at extinguishment (CFE) at or above 20 kW/m² measured according to ISO 5658-2 on a 3 mm thick plaque, resulting in R1 applications in compliance with Hazard Level 2 rating for the EN45545 (2013) standard. These values can be obtained in articles having a wide range of thicknesses, for example from 0.1 to 10 mm, or 0.5 to 5 mm.

The polycarbonate compositions can be formulated to have lower densities, in particular a density of 1.35 g/cc or less, 1.34 g/cc or less, 1.33 g/cc or less, 1.32 g/cc or less, 1.31 g/cc or less, 1.30 g/cc or less, or 1.29 g/cc or less. The same or similar values can be obtained in components having a wide range of thicknesses, for example from 0.1 to 10 mm, or 0.5 to 5 mm.

The polycarbonate compositions can further have good melt viscosities, which aid processing. The polycarbonate compositions can have a melt volume flow rate (MVR, cubic centimeter per 10 minutes (cc/10 min) of 4 to about 30, greater than or equal to 5, greater than or equal to 6, greater than or equal to 7, greater than or equal to 8, greater than or equal to 9, greater than or equal to 10, greater than or equal to 12, or greater than or equal to 14 cc/min, measured at 300° C./1.2 Kg at 360 second dwell according to ISO 1133. The same or similar values can be obtained in articles having a wide range of thicknesses, for example from 0.1 to 10 mm, or 0.5 to 5 mm.

The polycarbonate compositions can further have excellent impact properties, in particular multiaxial impact (MAI) and ductility. The compositions can have an MAI equal to or higher than 100 J, measured at 23° C. at an impact speed of 4.4 m/second according to ISO 6603 on discs with a thickness of 3.2 mm. The compositions can have a ductility in multiaxial impact of 80% and higher, specifically 100%, measured at 23° C. at an impact speed of 4.4 m/second according to ISO 6603 on discs with a thickness of 3.2 mm. These values can be obtained in articles having a wide range of thicknesses, for example from 0.1 to 10 mm, or 0.5 to 5 mm. In some embodiments, the composition can have an MAI equal to or higher than 100 J and a high ductility (80% or greater, for example 100%) at lower temperatures such as 10° C., 0° C., −10° C., −20° C. and −30° C.

As noted above the present discovery allows the manufacture of compositions have very low smoke densities (Ds-4), measured according to ISO5659-2 on a 3 mm thick plaque at 50 kW/m², and low heat release (MAHRE) measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², while maintaining the advantageous properties of polycarbonates. Thus, polycarbonate compositions having practical impact properties within 20%, within 10%, within 5%, or within 1% of the same compositions without the PC-siloxane or polydialkylsiloxane can be manufactured. For example, the polycarbonate compositions can have an MAI within 20%, within 10%, within 5%, or within 1% of the MAI of the same composition, each measured at 23° C. at an impact speed of 4.4 m/second according to ISO 6603 on discs with a thickness of 3.2 mm. The transmission property of the polycarbonate polymers can further be maintained in some embodiments.

Transportation components, in particular seat components and claddings for train interiors that are molded or extruded from the thermoplastic compositions are also provided. Molding can be by a variety of means such as injection molding, rotational molding, blow molding, and the like. In an embodiment, the molding is by injection molding. Illustrative claddings include, for example interior vertical surfaces, such as side walls, front walls, end-walls, partitions, room dividers, flaps, boxes, hoods and louvres; interior doors and linings for internal and external doors; window insulations, kitchen interior surfaces, interior horizontal surfaces, such as ceiling paneling, flaps, boxes, hoods and louvres; luggage storage areas, such as overhead and vertical luggage racks, luggage containers and compartments; driver's desk applications, such as paneling and surfaces of driver's desk; interior surfaces of gangways, such as interior sides of gangway membranes (bellows) and interior linings; window frames (including sealants and gaskets); (folding) tables with downward facing surface; interior and exterior surface of air ducts, and devices for passenger information (such as information display screens) and the like.

In an embodiment, the seat components and claddings meet certain criteria set forth in European Railway standard EN-45545 (2013). The European Union has approved the introduction of a set of fire testing standards for the railroad industry that prescribes certain flammability, flame spread rate, heat release, smoke emission, and smoke toxicity requirements for materials used in railway vehicles, known as European Railway standard EN-45545 (2013). Based on the vehicle material, end-use, and fire risks, 26 different “Requirement” categories for materials have been established (R1-R26). Seat components such as a back or base shell fall under the R6 application type. Lighting strips fall under the R3 application type. The R1 application type covers, amongst others, interior vertical surfaces, such as side walls, front walls, end-walls, partitions, room dividers, flaps, boxes, hoods and louvres; interior doors and linings for internal and external doors; window insulations, kitchen interior surfaces, interior horizontal surfaces, such as ceiling paneling, flaps, boxes, hoods and louvres; luggage storage areas, such as overhead and vertical luggage racks, luggage containers and compartments; driver's desk applications, such as paneling and surfaces of driver's desk; interior surfaces of gangways, such as interior sides of gangway membranes (bellows) and interior linings; window frames (including sealants and gaskets); (folding) tables with downward facing surface; interior and exterior surface of air ducts, and devices for passenger information (such as information display screens) and the like.

“Hazard Levels” (HL1 to HL3) have been designated, reflecting the degree of probability of personal injury as the result of a fire. The levels are based on dwell time and are related to operation and design categories. HL1 is the lowest hazard level and is typically applicable to vehicles that run under relatively safe conditions (easy evacuation of the vehicle). HL3 is the highest hazard level and represents most dangerous operation/design categories (difficult and/or time-consuming evacuation of the vehicle, e.g. in underground rail cars). For each application type, different test requirements for the hazard levels are defined. The testing methods, and smoke density and maximum heat release rate values for the various hazard levels in the European Railway standard EN-45545 (2013) are shown in Table 1A for R6 applications.

TABLE 1A European Railways Standard EN 45545 for R6 applications Hazard Smoke Density, DS-4 Heat release, MAHRE (kW/m²) Level ISO 5659-2 at 50 kW/m² ISO 5660-1 at 50 kW/m² HL1 ≦600 — HL2 ≦300 ≦90 HL3 ≦150 ≦60 The testing methods, and smoke density, maximum heat release rate values and critical heat flux at extinguishment for the various hazard levels in the European Railway standard EN-45545 (2013) are shown in Table 1B for R1 applications.

TABLE 1B European Railways Standard EN 45545 for R1 applications Smoke Density, Heat release, MAHRE Critical heat flux at DS-4 (kW/m²) extinguishment Hazard ISO 5659-2 at 50 ISO 5660-1 at 50 (CFE) [kW/m²] Level kW/m² kW/m² ISO 5658-2 HL1 ≦600 — >20 HL2 ≦300 ≦90 >20 HL3 ≦150 ≦60 >20

Data in the Examples shows that the compositions herein can meet the requirements for HL2, for both R1 and R6 applications.

While the compositions described herein are designed for use specifically in railway interiors, it is to be understood that the compositions are also useful in other interior components that are required to meet the test standards for HL2 for both R1 and R6 applications. Interior bus components are specifically mentioned. Current discussions directed to increasing bus safety include proposals to apply the HL2 standards to interior bus components. This invention accordingly includes interior bus components, including seat components and claddings as described above and comprising the specific compositions described herein, and particularly below, that meet the tests specified in the HL2 standards described above.

In an embodiment, provided herein is an a railway component wherein the component is a seat component, and wherein the railway component is molded or formed from a thermoplastic polymer composition comprising 50 to 93 wt. % of a poly(bisphenol A carbonate)-co-(bisphenol phthalate ester) (for example, comprising 75 to 85 wt. % of the ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate of 98:2 to 88:12, or comprising 35 to 45 wt. % of carbonate units and 55 to 65 wt. % of ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate of 45:55 to 55:45); 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing (specifically of formula 9b-2), wherein E has an average value of 2 to 200 (or 2 to 60, or 2 to 30), wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein an article having a thickness of 0.5 to 10 mm molded from the composition has a Ds-4 smoke density of less than or equal to 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², and a MAHRE of less than or equal to 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², a multiaxial impact energy at or above 100 J and a ductility of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second according to ISO 6603 on 3.2 mm thick discs, optionally a molded or formed sample of the thermoplastic polymer composition has a transmission of 80% or more or a haze of 5 or less, each measured using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm according to ASTM D1003, and optionally, a melt volume flow rate of greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133. Optionally, the seat component is injection molded, and the thermoplastic composition has a melt volume flow rate of equal to or greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133; or the seat component is extruded, and the thermoplastic composition has a Vicat B120 of less than 160° C. measured according to ISO 306.

In a specific embodiment, the foregoing composition comprises 4 to 20 wt. % of the poly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less, measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm. These transparencies can be achieved by use of a PC-siloxane comprising carbonate units (1) derived from bisphenol A, and repeating siloxane units (9b-2), (9b-3), (9b-4), or a combination comprising at least one of the foregoing (specifically of formula 9b-2), wherein E has an average value of 4 to 50, 4 to 15, specifically 5 to 15, more specifically 6 to 15, and still more specifically 7 to 10. The transparent PC-siloxanes can be manufactured using one or both of the tube reactor processes described in U.S. Patent Application No. 2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 may be used to synthesize the poly(siloxane-carbonate) copolymers.

In other specific embodiments of the foregoing seat components, one or more of the following conditions can apply: the thermoplastic composition can further comprise 5 to 20 wt. % of a bisphenol A polycarbonate; the organophosphorus compound can be an aromatic organophosphorus compound can have at least one organic aromatic group and at least one phosphorus-containing group, such as bisphenol A bis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate), tricresyl phosphate, a phenol/bi-phenol polyphosphate, or a combination comprising at least one of the foregoing, or an organic compound having at least one phosphorus-nitrogen bond such as a phosphazene, phosphorus ester amide, phosphoric acid amide, phosphonic acid amide, phosphinic acid amide, tris(aziridinyl)phosphine oxide, or a combination comprising at least one of the foregoing; optionally, the composition comprises 0.05 to 10.0 wt. % of a light diffuser additive comprising silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethyleneglycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing, based on the total weight of the polymers in the thermoplastic composition, or 0.00002 to 5.0 wt. % of one or more colorants based on the total weight of the polymers in the thermoplastic composition; or no or substantially no flame retarding brominated compounds, flame retardant salts, or a combination comprising at least one of the foregoing are present in the thermoplastic composition.

Also provided herein is a railway component wherein the component is a seat component, and wherein the railway component is molded or formed from a thermoplastic polymer composition comprising 50 to 93 wt. % of a polycarbonate copolymer comprising bisphenol A carbonate units and units of the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to five C₁₋₁₀ alkyl groups, or C₁₋₄ alkyl (specifically unsubstituted phenyl); 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing (specifically of formula 9b-2), wherein E has an average value of 2 to 200 (specifically 12 to 100, 2 to 60, or 3 to 30), wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing, wherein an article having a thickness of 0.5 to 10 mm molded from the composition has a Ds-4 smoke density of less than or equal to 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², and a MAHRE of less than or equal to 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², a multiaxial impact energy at or above 100 J and a ductility of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second according to ISO 6603 on 3.2 mm thick discs, and optionally, a melt volume flow rate of greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133. Optionally, the seat component is injection molded, and the thermoplastic composition has a melt volume flow rate of equal to or greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133; or the seat component is extruded, and the thermoplastic composition has a Vicat B120 of less than 160° C. measured according to ISO 306.

In a specific embodiment, the composition comprises 4 to 20 wt. % of the poly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm. These transparencies can be achieved by use of a PC-siloxane comprising carbonate units (1) derived from bisphenol A, and repeating siloxane units (9b-2), (9b-3), (9b-4), or a combination comprising at least one of the foregoing (specifically of formula 9b-2), wherein E has an average value of 4 to 50, 4 to 15, specifically 5 to 15, more specifically 6 to 15, and still more specifically 7 to 10. The transparent PC-siloxanes can be manufactured using one or both of the tube reactor processes described in U.S. Patent Application No. 2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 may be used to synthesize the poly(siloxane-carbonate) copolymers.

In other specific embodiments of the foregoing seat components, one or more of the following conditions can apply: the thermoplastic composition can further comprise 5 to 20 wt. % of a bisphenol A polycarbonate; the organophosphorus compound can be an aromatic organophosphorus compound can have at least one organic aromatic group and at least one phosphorus-containing group, such as bisphenol A bis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate), tricresyl phosphate, a phenol/bi-phenol polyphosphate, or a combination comprising at least one of the foregoing, or an organic compound having at least one phosphorus-nitrogen bond such as a phosphazene, phosphorus ester amide, phosphoric acid amide, phosphonic acid amide, phosphinic acid amide, tris(aziridinyl)phosphine oxide, or a combination comprising at least one of the foregoing; optionally, the composition comprises 0.05 to 10.0 wt. % of a light diffuser additive comprising silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethyleneglycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing, based on the total weight of the polymers in the thermoplastic composition, or 0.00002 to 5.0 wt. % of one or more colorants based on the total weight of the polymers in the thermoplastic composition; or no or substantially no flame retarding brominated compounds, flame retardant salts, or a combination comprising at least one of the foregoing are present in the thermoplastic composition.

Also provided herein is a railway component wherein the component is a cladding, in particular an interior vertical surface, such as side walls, front walls, end-walls, partitions, room dividers, flaps, boxes, hoods and louvres; an interior door or lining for internal and external doors; a window insulation, a kitchen interior surface, an interior horizontal surface, such as ceiling paneling, flaps, boxes, hoods and louvres; a luggage storage area, such as overhead and vertical luggage racks, luggage containers and compartments; a driver's desk application, such as paneling and surfaces of driver's desk; an interior surface of gangways, such as interior sides of gangway membranes (bellows) and interior linings; a window frame (including sealants and gaskets); a (folding) table with downward facing surface; an interior or exterior surface of air ducts, or a device for passenger information, such as information display screens, and wherein the railway component is molded or formed from a thermoplastic polymer composition comprising, based on the total weight of the composition, 50 to 93 wt. % of a poly(bisphenol A carbonate)-co-(bisphenol phthalate ester) (for example, comprising 75 to 85 wt. % of the ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate of 98:2 to 88:12, or comprises 35 to 45 wt. % of carbonate units and 55 to 65 wt. % of ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate of 45:55 to 55:45); 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing (specifically of formula 9b-2), wherein E has an average value of 2 to 200 (specifically, 2 to 100, 2 to 60, or 2 to 30), wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing, wherein an article having a thickness of 0.5 to 10 mm molded from the composition has a Ds-4 smoke density of less than or equal to 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², and a MAHRE of less than or equal to 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², a critical heat flux at extinguishment (CFE) of equal to or more than 20 kW/m² measured according to ISO 5658-2 at a 3 mm thick plaque, a multiaxial impact energy at or above 100 J and a ductility of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second according to ISO 6603 on 3.2 mm thick discs, and optionally, a melt volume flow rate of greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133. Optionally, the cladding is injection molded, and the thermoplastic composition has a melt volume flow rate of equal to or greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133; or the cladding is extruded, and the thermoplastic composition has a Vicat B120 of less than 160° C. measured according to ISO 306.

In a specific embodiment, the composition comprises 4 to 20 wt. % of the poly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm. These transparencies can be achieved by use of a PC-siloxane comprising carbonate units (1) derived from bisphenol A, and repeating siloxane units (9b-2), (9b-3), (9b-4), or a combination comprising at least one of the foregoing (specifically of formula 9b-2), wherein E has an average value of 4 to 50, 4 to 15, specifically 5 to 15, more specifically 6 to 15, and still more specifically 7 to 10. The transparent PC-siloxanes can be manufactured using one or both of the tube reactor processes described in U.S. Patent Application No. 2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 may be used to synthesize the poly(siloxane-carbonate) copolymers.

In other specific embodiments of the foregoing claddings, one or more of the following conditions can apply: the thermoplastic composition can further comprise 5 to 20 wt. % of a bisphenol A polycarbonate; the organophosphorus compound can be an aromatic organophosphorus compound can have at least one organic aromatic group and at least one phosphorus-containing group, such as bisphenol A bis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate), tricresyl phosphate, a phenol/bi-phenol polyphosphate, or a combination comprising at least one of the foregoing, or an organic compound having at least one phosphorus-nitrogen bond such as a phosphazene, phosphorus ester amide, phosphoric acid amide, phosphonic acid amide, phosphinic acid amide, tris(aziridinyl)phosphine oxide, or a combination comprising at least one of the foregoing; optionally, the composition comprises 0.05 to 10.0 wt. % of a light diffuser additive comprising silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethyleneglycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing, based on the total weight of the polymers in the thermoplastic composition, or 0.00002 to 5.0 wt. % of one or more colorants based on the total weight of the polymers in the thermoplastic composition; or no or substantially no flame retarding brominated compounds, flame retardant salts, or a combination comprising at least one of the foregoing are present in the thermoplastic composition.

Specifically, the cladding can be a side wall, a front wall, an end-wall, a partition, a room divider, an interior door, a window insulation, a lining, a kitchen interior surface, a ceiling panel, an overhead or vertical luggage rack, a luggage container, a luggage compartment, a window frame, an optionally folding table with downward facing surface, or an information display screen. The cladding can also be a partition, a room divider, an interior door or lining for internal and external doors, a window insulation, an overhead and vertical luggage rack, a luggage container and compartment, a window frame; an optionally folding table with downward facing surface; or a device for passenger information wherein the cladding has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm. In another embodiment, the cladding is a partition, a room divider, an interior door or lining for internal and external doors, a window insulation, an overhead and vertical luggage rack, a luggage container and compartment, a window frame, an optionally folding table with downward facing surface, or a device for passenger information, wherein the composition comprises a light diffuser additive comprising a silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethyleneglycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing.

Also provided herein is a railway component wherein the component is an interior vertical surface, such as side walls, front walls, end-walls, partitions, room dividers, flaps, boxes, hoods and louvres; an interior door or lining for internal and external doors; a window insulation, a kitchen interior surface, an interior horizontal surface, such as ceiling paneling, flaps, boxes, hoods and louvres; a luggage storage area, such as overhead and vertical luggage racks, luggage containers and compartments; a driver's desk application, such as paneling and surfaces of driver's desk; an interior surface of gangways, such as interior sides of gangway membranes (bellows) and interior linings; a window frame (including sealants and gaskets); a (folding) table with downward facing surface; an interior or exterior surface of air ducts, or a device for passenger information, such as information display screens, and wherein the railway component is molded or formed from a thermoplastic polymer composition comprising, based on the total weight of the composition, 50 to 93 wt. % of a polycarbonate copolymer comprising bisphenol A carbonate units and units of the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to five C₁₋₁₀ alkyl groups, or C₁₋₄ alkyl (specifically unsubstituted phenyl); 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing (specifically of formula 9b-2), wherein E has an average value of 2 to 200 (specifically 2 to 100, 2 to 60 or 2 to 30), wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein an article having a thickness of 0.5 to 10 mm molded from the composition has a Ds-4 smoke density of less than or equal to 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², and a MAHRE of less than or equal to 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², a critical heat flux at extinguishment (CFE) of equal to or more than 20 kW/m² measured according to ISO 5658-2 at a 3 mm thick plaque, a multiaxial impact energy at or above 100 J and a ductility of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second according to ISO 6603 on 3.2 mm thick discs, optionally, a melt volume flow rate of greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133. Optionally, the cladding is injection molded, and the thermoplastic composition has a melt volume flow rate of equal to or greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133; or the cladding is extruded, and the thermoplastic composition has a Vicat B120 of less than 160° C. measured according to ISO 306.

In a specific embodiment, the composition comprises 4 to 20 wt. % of the poly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm. These transparencies can be achieved by use of a PC-siloxane comprising carbonate units (1) derived from bisphenol A, and repeating siloxane units (9b-2), (9b-3), (9b-4), or a combination comprising at least one of the foregoing (specifically of formula 9b-2), wherein E has an average value of 4 to 50, 4 to 15, specifically 5 to 15, more specifically 6 to 15, and still more specifically 7 to 10. The transparent PC-siloxanes can be manufactured using one or both of the tube reactor processes described in U.S. Patent Application No. 2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 may be used to synthesize the poly(siloxane-carbonate) copolymers.

In other specific embodiments of the foregoing claddings, one or more of the following conditions can apply: the thermoplastic composition can further comprise 5 to 20 wt. % of a bisphenol A polycarbonate; the organophosphorus compound can be an aromatic organophosphorus compound can have at least one organic aromatic group and at least one phosphorus-containing group, such as bisphenol A bis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate), tricresyl phosphate, a phenol/bi-phenol polyphosphate, or a combination comprising at least one of the foregoing, or an organic compound having at least one phosphorus-nitrogen bond such as a phosphazene, phosphorus ester amide, phosphoric acid amide, phosphonic acid amide, phosphinic acid amide, tris(aziridinyl)phosphine oxide, or a combination comprising at least one of the foregoing; optionally, the composition comprises 0.05 to 10.0 wt. % of a light diffuser additive comprising silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethyleneglycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing, based on the total weight of the polymers in the thermoplastic composition, or 0.00002 to 5.0 wt. % of one or more colorants based on the total weight of the polymers in the thermoplastic composition; or no or substantially no flame retarding brominated compounds, flame retardant salts, or a combination comprising at least one of the foregoing are present in the thermoplastic composition.

Specifically, the cladding can be a side wall, a front wall, an end-wall, a partition, a room divider, an interior door, a window insulation, a lining, a kitchen interior surface, a ceiling panel, an overhead or vertical luggage rack, a luggage container, a luggage compartment, a window frame, an optionally folding table with downward facing surface, or an information display screen. The cladding can also be a partition, a room divider, an interior door or lining for internal and external doors, a window insulation, an overhead and vertical luggage rack, a luggage container and compartment, a window frame; an optionally folding table with downward facing surface; or a device for passenger information wherein the cladding has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm. In another embodiment, the cladding is a partition, a room divider, an interior door or lining for internal and external doors, a window insulation, an overhead and vertical luggage rack, a luggage container and compartment, a window frame, an optionally folding table with downward facing surface, or a device for passenger information, wherein the composition comprises a light diffuser additive comprising a silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethyleneglycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing

In any of the foregoing embodiments of the seat components or claddings, a sample molded from these compositions can have a smoke density after 4 minutes (DS-4) of less than 300, less than 250, or less than 200 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m². A sample molded from these compositions can also have a heat release (MAHRE) of less than 90 kW/m², less than 80 kW/m², less than 70 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m². Furthermore, the polycarbonate compositions can have a melt volume flow rate (MVR, cubic centimeter per 10 minutes (cc/10 min) of 4 to about 15, measured at 300° C./1.2 Kg at 360 second dwell according to ISO 1133. The polycarbonate compositions can have an MAI equal to or higher than 100 J, measured at 23° C. at an impact speed of 4.4 m/second according to ISO 6603 on discs with a thickness of 3.2 mm. The polycarbonate compositions can have a ductility in multiaxial impact of 80% and higher, for example 100%, measured at 23° C. at an impact speed of 4.4 m/second according to ISO 6603 on discs with a thickness of 3.2 mm. The polycarbonate compositions can have a critical heat flux at extinguishment (CFE) of equal to or more than 20 kW/m² measured according to ISO 5658-2 at a 3 mm thick plaque.

In some embodiments a combination of a bisphenol A polycarbonate and an arylate ester can be used in place of the poly(bisphenol A carbonate)-co-(bisphenol phthalate ester). In these embodiments a molded or extruded train seat component comprises a thermoplastic composition comprising, based on the total weight of the composition: 50 to 93 wt. % of a combination comprising i) 5 to 50 wt. %, or 35 to 45 wt. % of a bisphenol A polycarbonate and (ii) 50 to 95 wt. %, specifically 55 to 65 wt. % of a poly(bisphenol A arylate), specifically a poly(bisphenol A arylate), based on the weight of the combination; and 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula (9b-2), (9b-3), (9b-4), or a combination comprising at least one of the foregoing (specifically of formula 9b-2), wherein E has an average value of 2 to 200 (specifically, 2 to 100, 2 to 60, or 2 to 30); and 3 to 20 wt. % of an organophosphorus compound, in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein the component has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs. Optionally, the seat component is injection molded, and the thermoplastic composition has a melt volume flow rate of equal to or greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133, or the seat component is extruded, and formed, and the thermoplastic composition has a Vicat B120 of less than 140° C. measured according to ISO 306.

Optionally, the thermoplastic composition can comprise from 4 to 20 wt. % of the poly(carbonate-siloxane) comprising from 1 to 10 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane), wherein a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm.

In other specific embodiments of the foregoing seat components, one or more of the following conditions can apply: the thermoplastic composition can further comprise 5 to 20 wt. % of a bisphenol A polycarbonate; the organophosphorus compound can be an aromatic organophosphorus compound can have at least one organic aromatic group and at least one phosphorus-containing group, such as bisphenol A bis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate), tricresyl phosphate, a phenol/bi-phenol polyphosphate, or a combination comprising at least one of the foregoing, or an organic compound having at least one phosphorus-nitrogen bond such as a phosphazene, phosphorus ester amide, phosphoric acid amide, phosphonic acid amide, phosphinic acid amide, tris(aziridinyl)phosphine oxide, or a combination comprising at least one of the foregoing; optionally, the composition comprises 0.05 to 10.0 wt. % of a light diffuser additive comprising silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethyleneglycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing, based on the total weight of the polymers in the thermoplastic composition, or 0.00002 to 5.0 wt. % of one or more colorants based on the total weight of the polymers in the thermoplastic composition; or no or substantially no flame retarding brominated compounds, flame retardant salts, or a combination comprising at least one of the foregoing are present in the thermoplastic composition.

Also provided herein is a railway component wherein the component is a cladding, in particular an interior vertical surface, such as side walls, front walls, end-walls, partitions, room dividers, flaps, boxes, hoods and louvres; an interior door or lining for internal and external doors; a window insulation, a kitchen interior surface, an interior horizontal surface, such as ceiling paneling, flaps, boxes, hoods and louvres; a luggage storage area, such as overhead and vertical luggage racks, luggage containers and compartments; a driver's desk application, such as paneling and surfaces of driver's desk; an interior surface of gangways, such as interior sides of gangway membranes (bellows) and interior linings; a window frame (including sealants and gaskets); a (folding) table with downward facing surface; an interior or exterior surface of air ducts, or a device for passenger information, such as information display screens, and wherein the railway component is molded or formed from a thermoplastic polymer composition comprising, based on the total weight of the composition: 50 to 93 wt. % of a combination comprising i) 5 to 50 wt. %, or 35 to 45 wt. % of a bisphenol A polycarbonate and (ii) 50 to 95 wt. %, specifically 55 to 65 wt. % of a poly(bisphenol A arylate), specifically a poly(bisphenol A arylate), based on the weight of the combination; and 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula (9b-2), (9b-3), (9b-4), or a combination comprising at least one of the foregoing (specifically of formula 9b-2), wherein E has an average value of 2 to 200 (specifically, 2 to 100, 2 to 60, or 2 to 30); and 3 to 20 wt. % of an organophosphorus compound, in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein the component has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs. Optionally, the cladding is injection molded, and the thermoplastic composition has a melt volume flow rate of equal to or greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133, or the seat component is extruded, and formed, and the thermoplastic composition has a Vicat B120 of less than 140° C. measured according to ISO 306.

Optionally, the thermoplastic composition can comprise from 4 to 20 wt. % of the poly(carbonate-siloxane) comprising from 1 to 10 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane), wherein a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm.

In other specific embodiments of the foregoing claddings, one or more of the following conditions can apply: the thermoplastic composition can further comprise 5 to 20 wt. % of a bisphenol A polycarbonate; the organophosphorus compound can be an aromatic organophosphorus compound can have at least one organic aromatic group and at least one phosphorus-containing group, such as bisphenol A bis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate), tricresyl phosphate, a phenol/bi-phenol polyphosphate, or a combination comprising at least one of the foregoing, or an organic compound having at least one phosphorus-nitrogen bond such as a phosphazene, phosphorus ester amide, phosphoric acid amide, phosphonic acid amide, phosphinic acid amide, tris(aziridinyl)phosphine oxide, or a combination comprising at least one of the foregoing; optionally, the composition comprises 0.05 to 10.0 wt. % of a light diffuser additive comprising silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethyleneglycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing, based on the total weight of the polymers in the thermoplastic composition, or 0.00002 to 5.0 wt. % of one or more colorants based on the total weight of the polymers in the thermoplastic composition; or no or substantially no flame retarding brominated compounds, flame retardant salts, or a combination comprising at least one of the foregoing are present in the thermoplastic composition.

Specifically, the cladding can be a side wall, a front wall, an end-wall, a partition, a room divider, an interior door, a window insulation, a lining, a kitchen interior surface, a ceiling panel, an overhead or vertical luggage rack, a luggage container, a luggage compartment, a window frame, an optionally folding table with downward facing surface, or an information display screen. The cladding can also be a partition, a room divider, an interior door or lining for internal and external doors, a window insulation, an overhead and vertical luggage rack, a luggage container and compartment, a window frame; an optionally folding table with downward facing surface; or a device for passenger information wherein the cladding has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm. In another embodiment, the cladding is a partition, a room divider, an interior door or lining for internal and external doors, a window insulation, an overhead and vertical luggage rack, a luggage container and compartment, a window frame, an optionally folding table with downward facing surface, or a device for passenger information, wherein the composition comprises a light diffuser additive comprising a silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethyleneglycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing.

In still another embodiment, a molded or extruded train seat component comprises a thermoplastic composition comprising, based on the total weight of the composition: 75 to 96.5 wt. % of a poly(bisphenol A carbonate)-co-(bisphenol phthalate ester) (for example, comprising 75 to 85 wt. % of the ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate of 98:2 to 88:12, or comprises 35 to 45 wt. % of carbonate units and 55 to 65 wt. % of ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate of 45:55 to 55:45); 0.5 to 5 wt. %, specifically 0.5 to 3 wt. %, of a poly(siloxane) oil (for example a poly(dimethyl siloxane) oil); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein the component has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs. Optionally, the seat component is injection molded, and the thermoplastic composition has a melt volume flow rate of equal to or greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133, or the seat component is extruded, and formed, and the thermoplastic composition has a Vicat B120 of less than 140° C. measured according to ISO 306.

Alternatively, an extruded or molded interior train cladding comprises a thermoplastic composition comprising, based on the total weight of the composition: 75 to 96.5 wt. % of a poly(bisphenol A carbonate)-co-(bisphenol phthalate ester) (for example, comprising 75 to 85 wt. % of the ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate of 98:2 to 88:12, or comprises 35 to 45 wt. % of carbonate units and 55 to 65 wt. % of ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate of 45:55 to 55:45); 0.5 to 5 wt. %, specifically 0.5 to 3 wt. %, of a poly(siloxane) oil (for example a poly(dimethyl siloxane) oil); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein the component has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs. Optionally, the seat component is injection molded, and the thermoplastic composition has a melt volume flow rate of equal to or greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO 1133, or the seat component is extruded, and formed, and the thermoplastic composition has a Vicat B120 of less than 140° C. measured according to ISO 306.

The seat components or cladding having low smoke density and low heat release rates are further illustrated by the following non-limiting examples.

EXAMPLES

The materials used in the Examples are described in Table 2A.

TABLE 2A Component Chemical Description Source PC1 Linear Bisphenol A Polycarbonate, produced via interfacial polymerization, SABIC Mw of about 30,000 g/mol as determined by GPC using polycarbonate standards, phenol end-capped PC2 Linear Bisphenol A Polycarbonate, produced via interfacial polymerization, SABIC Mw of about 21,800 g/mol as determined by GPC using polycarbonate standards, phenol end-capped PC3 Branched Bisphenol A polycarbonate, produced via interfacial SABIC polymerization, 0.3 mol % 1,1,1-tris(4-hydroxyphenyl)ethane (THPE) branching agent, Mw about 33,600 g/mol as determined by GPC using polycarbonate standards, para-cumylphenol (PCP) end-capped PC4 Linear Bisphenol A Polycarbonate, produced via interfacial polymerization, SABIC Mw of about 18,800 g/mol as determined by GPC using polycarbonate standards, para-cumylphenyl (PCP) end-capped PPP-BP/BPA PPP-BP (N-phenylphenolphthaleinylbisphenol, 2,2-bis(4-hydro)-Bisphenol SABIC A Polycarbonate copolymer, produced via interfacial polymerization, 32 mol % PPP-BP, Mw about 25,000 g/mol as determined by GPC using polycarbonate standards, para-cumylphenol (PCP) end-capped SiPC1 PDMS (polydimethylsiloxane)-Bisphenol A Polycarbonate copolymer, SABIC produced via interfacial polymerization, 20 wt. % siloxane containing eugenol endcaps, average PDMS block length of 45 units (D45), Mw about 30,000 g/mol as determined by GPC using polycarbonate standards, para-cumylphenol (PCP) end-capped* SiPC2 PDMS (polydimethylsiloxane)-Bisphenol A Polycarbonate copolymer, SABIC produced via interfacial polymerization, 6 wt. % siloxane containing eugenol endcaps, average PDMS block length of 45 units (D45), Mw about 23,000 g/mol as determined by GPC using polycarbonate standards, para- cumylphenol (PCP) end-capped* SiPC3 PDMS (polydimethylsiloxane)-Bisphenol A Polycarbonate copolymer, SABIC produced via interfacial polymerization, 1 wt. % siloxane containing eugenol endcaps, average PDMS block length of 10 units (D10), Mw about 22,500 g/mol as determined by GPC using polycarbonate standards, para- cumylphenol (PCP) end-capped SiPC4 PDMS (polydimethylsiloxane)-Bisphenol A Polycarbonate copolymer, SABIC produced via interfacial polymerization, 20 wt. % siloxane containing eugenol endcaps, average PDMS block length of 90 units (D90), Mw about 30.000 g/mol as determined by GPC using Polycarbonate standards, para-cumylphenol (PCP) end-capped PC-Ester1 Poly(phthalate-carbonate) copolymer, produced via interfacial SABIC polymerization, about 81 mol % ester units, Mw about 28,500 g/mol as determined via GPC using polycarbonate standards, para-cumylphenol (PCP) end-capped PC-Ester2 Poly(phthalate-carbonate) copolymer, produced via interfacial SABIC polymerization, about 60 mol % ester units, Mw about 35,400 g/mol as determined via GPC using polycarbonate standards, para-cumylphenol (PCP) end-capped PDMS 100 Polydimethylsiloxane (PDMS) oil, M100 (100 cps) MOMENTIVE PDMS 350 Polydimethylsiloxane (PDMS) oil, M350 (350 cps) MOMENTIVE PDMS 1000 Polydimethylsiloxane (PDMS) oil, M1000 (1000 cps) MOMENTIVE PMPS Polyphenylmethylsiloxane oil, PN200 MOMENTIVE OPCTS Octaphenylcyclotetrasiloxane MOMENTIVE PEI Polyetherimide resin, made via reaction of bisphenol A dianhydride with SABIC equimolar amount of m-phenylene diamine, Mw about 33,000 g/mol, determined via GPC using Polystyrene standards PPSU Radel 5100; poly(phenylenesulfone) SOLVAY BPADP Bisphenol A diphosphate Nagase (Europe) GmbH TiO₂ Coated titanium dioxide DuPont Titanium Carbon black Amorphous Carbon Cabot GAFOS 168 Tris(di-t-butylphenyl)phosphite BASF IRGANOX Octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate BASF 1076 PC105BR TetrabromoBPA/bisphenol A polycarbonate copolymer, bromine content of SABIC 26 wt. %, Mw about 23,700 g/mol, para-cumyl phenol end-capped KSS Potassium 3-(phenylsulfonyl)benzenesulfonate Sloss Industries Corporation Rimar Potassium nonafluoro-l-butanesulfonate Lanxess Germany PTFE Encapsulated PTFE SABIC ABS R360 Acrylonitrile-butadiene-styrene resin, 360, butadiene content 51.8%, styrene SABIC content 36.9%, acrylonitrile content 11.3% *Can be manufactured by the methods described in U.S. 6,072,011 to Hoover.

The tests performed are summarized in Table 2B.

TABLE 2B Description Test Conditions Specimen Property Units ISO Smoke density ISO 5659-2 50 kW/m² plaque 75 × 75 × 3 DS-4 [—] mm ISO Heat release ISO 5660-1 50 kW/m² plaque 100 × 100 × 3 MAHRE kW/m² mm ISO Flame spread ISO 5658-2 plaque 800 × 155 × 3 CFE kW/m² mm Melt volume rate ISO 1133 300° C., 1.2 Pellets MVR cm³/10 min kg, dwell time 300 s Melt viscosity ISO 1143 300° C., shear Pellets MV Pa.s rate of 1500 s⁻¹ Multiaxial Impact, ISO 6603 4.4 m/s, Disc, 3.2 mm MAI J (Energy), % Energy and temperatures thickness, 100 mm (Ductility) Ductility of 23° C. and diameter 0° C. Vicat, B120 ISO 306 B120 Multi-purpose ISO Vicat ° C. 3167 Type A, 4 mm thickness Transmission ASTM D1003 plaque 75 × 75 × 3 Transmission % mm Haze ASTM D1003 plaque 75 × 75 × 3 Haze — mm

Blending, Extrusion, and Molding Conditions

The compositions were made as follows. All solid additives (e.g., stabilizers, colorants, solid flame retardants) were dry blended off-line as concentrates using one of the primary polymer powders as a carrier and starve-fed via gravimetric feeder(s) into the feed throat of the extruder. The remaining polymer(s) were starve-fed via gravimetric feeder(s) into the feed throat of the extruder as well. The liquid flame retardants (e.g., BPADP) were fed before the vacuum using a liquid injection system. It will be recognized by one skilled in the art that the method is not limited to these temperatures or processing equipment.

Extrusion of all materials was performed on a 25 mm Werner-Pfleiderer ZAK twin-screw extruder (L/D ratio of 33/1) with a vacuum port located near the die face. The extruder has 9 zones, which were set at temperatures of 40° C. (feed zone), 200° C. (zone 1), 250° C. (zone 2), 270° C. (zone 3) and 280-300° C. (zone 4 to 8). Screw speed was 300 rpm and throughput was between 15 and 25 kg/hr. It will be recognized by one skilled in the art that the method is not limited to these temperatures or processing equipment.

The compositions were molded after drying at 100-110° C. for 6 hours on a 45-ton Engel molding machine with 22 mm screw or 75-ton Engel molding machine with 30 mm screw operating at a temperature 270-300° C. with a mold temperature of 70-90° C. It will be recognized by one skilled in the art that the method is not limited to these temperatures or processing equipment.

ISO smoke density measurements were performed on 7.5×7.5 cm plaques with 3 mm thickness using an NBS Smoke Density Chamber from Fire Testing Technology Ltd (West Sussex, United Kingdom). All measurements were performed according to ISO 5659-2, with an irradiance of 50 kW/m² at the sample position and a sample-to-cone distance of 5 cm in view of the charring behavior of the samples (as prescribed by ISO 5659-2). DS-4 was determined as the measured smoke density after 240 seconds. The tests executed are indicative tests. They were performed according to the ISO5659-2 standard, but were not executed by an officially certified test institute.

ISO heat release measurements were performed on 10×10 cm plaques with 3 mm thickness using a Cone calorimeter. All measurements were performed according to ISO 5660-1, with 50 kW/m² irradiance at the sample position and a sample-to-cone distance of 6 cm in view of the charring behavior of the samples (as prescribed by ISO 5660-1). Heat release is measured as MAHRE in kW/m² as prescribed by ISO5660-1. The tests executed are indicative tests, and were executed by an officially certified test institute.

ISO flame spread measurements were performed on an 800×155 mm plaques with 3 mm thickness using according to ISO 5658-2. Flame spread is measured as critical heat flux at extinguishment (CFE) in kW/m² as prescribed by ISO 5658-2. The tests executed are official tests executed by an officially certified test institute according to ISO 5658-2. Silicon content is a weight percent calculated by dividing the total weight of silicon atoms in a composition over the total weight of the composition.

Examples 1-13

Examples 1-13 demonstrate the effect of the addition of various polycarbonate-siloxane copolymers and polydimethylsiloxane (PDMS) oil to PPP-BP/BPA copolymers on smoke density, transparency, and haze properties. Formulations and results are shown in Table 3. The results are also illustrated graphically in FIGS. 1 and 2. Comparative Examples 1 and 6 show that both PPP-BP/BPA copolymer and polydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. % siloxane units (SiPC2) have relatively high smoke densities (DS-4) at 50 kW/m², measured according to ISO5659-2, far exceeding Hazard Level 2 requirements for EN45545 R1 or R6 applications (DS-4<300 at 50 kW/m²). Surprisingly, when relatively low amounts of SiPC2 are added to PPP-BP/BPA copolymer, the DS-4 values of the composition containing both SiPC2 and PPP-BP/BPA decrease significantly (Examples 2-4) as compared to compositions containing SiPC2 but not PPP-BP/BPA (Comparative Example 6) and compositions containing PPP-BP/BPA but not SiPC2 (Comparative Example 1).

Furthermore, there is an optimum in the amount of SiPC2 that may be added, on the smoke density improvement. FIG. 1 shows that for concentrations of SiPC2 above 10 wt. %, the smoke density values start to increase again. For the optimum SiPC2 loadings, the smoke density is reduced to such an extent that obtained DS-4 values for compositions containing SiPC2 and PPP-BP/BPA are below the HL2 thresholds for EN45545 R1 or R6 HL-2 qualifying applications (DS-4<300 at 50 kW/m²). Too high SiPC2 loadings (>20 wt. %) result in a higher DS-4 value far exceeding the DS-4 threshold of 300 at 50 kW/m² for HL2 compliant R1 or R6 applications.

The improvement in smoke density is also observed when other polydimethylsiloxane/bisphenol A polycarbonate copolymer types are added to the PPP-BP/BPA copolymer, as can be seen for both polydimethylsiloxane/bisphenol A polycarbonate copolymer having 20 wt. % siloxane units, (SiPC1, examples 7-9) and polydimethylsiloxane/bisphenol A polycarbonate copolymer having 1 wt. % siloxane units (SiPC3, Examples 10 and 11). There are some differences in the ability of different polydimethylsiloxane/bisphenol A polycarbonate copolymer types to reduce smoke density of PPP-BP/BPA copolymer even at similar silicon contents. Nonetheless, the addition of optimal amounts of SiPC1, SiPC2 and SiPC3 to PPP-BP/BPA copolymer reduces the smoke density to such an extent that obtained DS-4 values for compositions containing PPP-BP/BPA and SiPC are close to or below the thresholds HL-2 applications (DS-4<300 at 50 kW/m²).

Using relatively small amounts of either polydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. % siloxane units (SiPC2, 10 wt. % max) or polydimethylsiloxane/bisphenol A polycarbonate copolymer having 1 wt. % siloxane units (SiPC3) retains the relatively high transmission values of PPP-BP/BPA copolymer of 80% and higher and keeps the haze increase to acceptable levels below 5. The addition of the polydimethylsiloxane/bisphenol A polycarbonate copolymer having 20 wt. % siloxane units, on the other hand, results in significant reduction in transmission and increase in haze because of the opaque nature of this SiPC type. As such, addition of SiPC1 to PPP-BP/BPA copolymer to reduce smoke density in rail components to meet EN45545 R3, R1 or R6 qualifying application is only suitable when targeting non-transparent applications. The same is true for SiPC2, if the loadings are above 10 wt. %. In general, transparent compositions can be tuned by the amount of polydimethylsiloxane/bisphenol A polycarbonate copolymer and its architecture.

From Comparative Examples 12 and 13, it is evident that polydimethylsiloxane (PDMS) oil results only in minor reductions in smoke density of PPP-BP/BPA, much less than observed for any of the polydimethylsiloxane/bisphenol A polycarbonate copolymers at similar silicon content. Furthermore, the PPP-BP/BPA samples turn completely opaque after PDMS oil is added, since PDMS is not miscible with the PPP-BP/BPA copolymer. As such, polydimethylsiloxane/bisphenol A polycarbonate copolymers are much more suitable for reducing the smoke density of PPP-BP/BPA copolymers than PDMS oil, despite the similar nature of the siloxane (polydimethylsiloxane).

Examples 30-53

Examples 30-53 demonstrate the effect of the addition of various polydimethylsiloxane/bisphenol A polycarbonate copolymers and polysiloxanes to poly(phthalate-carbonate) copolymer (PC-Ester1) on smoke density, transmission, and haze.

Examples 30-37

These examples show the effect of adding polydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. % siloxane units (SiPC2) to poly(phthalate-carbonate) copolymer having 81 mol % ester units (PC-Ester1). Formulations and results are shown in Table 6. The results are illustrated graphically in FIG. 3.

TABLE 6 Unit CEx 30 Ex 31 Ex 32 Ex 33 Ex 34 Ex 35 CEx 36 CEx 37 Component PC-Ester1 Wt. % 100.00 94.95 89.95 82.45 74.95 67.45 59.95 SiPC2 Wt. % 5.00 10.00 17.50 25.00 32.50 40.00 100 Irgafos 168 Wt. % 0.05 0.05 0.05 0.05 0.05 0.05 Si content Wt. % 0.00 0.10 0.21 0.36 0.52 0.68 0.83 2.08 Property Smoke density, DS-4 — 1140 269 308 286 219 389 983 930 Transmission % 87.7 86.3 79.9 61.8 50.9 42.5 38.1 87.6 Haze — 1.42 2.12 6.56 28.8 49 67.4 77.9 2.48

Comparative Examples 30 and 37 show that both poly(phthalate-carbonate) copolymer having 81 mol % ester units (PC-Ester1) and polydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. % siloxane units (SiPC2) have a smoke density value (DS-4) that is high (1140 and 930 at 50 kW/m², respectively for comparative examples 30 and 37), to the point where compositions made from PC-Ester1 alone or SiPC2 alone would not comply with the EN45545 rail standard (2013) threshold for qualifying under R1 or R6 material selection criteria for any Hazard Level (HL) applications (DS-4<600 for HL-1, DS-4<300 for HL2 and DS-4<150 for HL3, all at 50 kW/m²).

Again, adding small amounts of SiPC2 to PC-Ester1 decreases the smoke density values significantly (Examples 31-35). The decrease in smoke density is dependent on the SiPC2 content, with DS-4 values below 300 at 50 kW/m² for SiPC2 loadings between 5 and 25% (Examples 31-35). As illustrated graphically in FIG. 3, too high SiPC2 loadings result in a too high DS-4 value (983 at 50 kW/m²) again (Comparative Example 36), similar to the DS-4 value of pure SiPC2 (930 at 50 kW/m², Comparative Example 37). The addition of optimal amounts of SiPC2 to PC-Ester1 reduces the smoke density to such an extent that obtained DS-4 values for compositions containing PC-Ester1 and SiPC2 are close to or below the thresholds for EN45545 R1 or R6 HL-2 applications (DS-4<300 at 50 kW/m²).

The addition of SiPC2 to PC-Ester1 reduces the transmission and increases the haze with increasing SiPC2 contents. At low SiPC2 contents, the reduction in transmission is relatively limited with transmission values of 80% and higher and haze values of 10 and lower. By optimizing the polydimethylsiloxane/bisphenol A polycarbonate copolymer content and its architecture, a combination of both low smoke density and acceptable optical properties can be achieved.

Examples 38-44 and 47-53

These examples demonstrate the effect of adding different polydimethylsiloxane/bisphenol A polycarbonate copolymer and polysiloxanes to poly(phthalate-carbonate) copolymer having 81 mol % ester units (PC-Ester 1) on smoke density. Formulations and results are shown in Table 7. The results are also graphically illustrated in FIGS. 6 and 7.

Examples 37-44 demonstrate the effect of adding different polydimethylsiloxane/bisphenol A polycarbonate copolymers having different mol percentages of siloxane units (SiPC1, 2, 3, and 4) to poly(phthalate-carbonate) copolymer

TABLE 3 Unit CEx 1 Ex 2 Ex 3 Ex 4 CEx 5 CEx 6 CEx 7 Ex 8 Ex 9 Ex 10 CEx 11 CEx 12 CEx 13 Component PPP-BP/BPA Wt. % 100.00 89.95 79.95 69.95 59.95 96.95 93.95 89.95 83.45 66.65 99.4 98.57 SiPC2 Wt. % 10.00 20.00 30.00 40.00 100.00 SiPC1 Wt. % 3.00 6.00 10.00 SiPC3 Wt. % 16.50 33.30 PDMS 1000 Wt. % 0.55 1.38 Irgafos 168 Wt. % 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 Si content Wt. % 0.00 0.21 0.42 0.62 0.83 2.08 0.21 0.42 0.69 0.06 0.13 0.21 0.52 Property Smoke density, — 626 237 323 415 421 935 545 341 218 366 567 587 569 DS-4 Transparency % 88.4 81.9 67.7 53.6 6 87.6 36.2 28.3 21.4 88.4 88.6 30.6 24.7 Haze — 1.14 3.8 18.1 42.8 19.0 2.48 104 104 104 0.78 0.89 104 104

TABLE 7 Unit Ex 38 Ex 39 Ex 40 Ex 41 Ex 42 Ex 43 Ex 44 Component PC-Ester 1 Wt. % 96.88 92.38 87.88 74.88 49.88 96.88 92.38 SiPC1 Wt. % 3.00 7.50 12.00 SiPC3 Wt. % 25.00 50.00 SiPC4 Wt. % 3.00 7.50 PDMS 1000 Wt. % PMPS Wt. % OPCTS Wt. % Irgafos 168 Wt. % 0.08 0.08 0.08 0.08 0.08 0.08 0.08 Antioxidant 1076 Wt. % 0.04 0.04 0.04 0.04 0.04 0.04 0.04 Si content Wt. % 0.21 0.52 0.83 0.09 0.19 0.21 0.53 Property Smoke density, DS-4 — 388 263 280 592 354 346 239 Transmission % 39.7 27.7 20.1 89.7 89.4 36.7 24.2 Haze — 97.4 104 104 0.55 0.64 104 104 CEx 47 Ex 48 Ex 49 CEx 50 CEx 51 CEx 52 CEx 53 Component PC-Ester 1 99.33 98.50 97.68 98.85 97.36 98.39 96.19 SiPC1 SiPC3 SiPC4 PDMS 1000 0.55 1.38 2.20 PMPS 1.03 2.52 OPCTS 1.49 3.69 Irgafos 168 0.08 0.08 0.08 0.08 0.08 0.08 0.08 Antioxidant 1076 0.04 0.04 0.04 0.04 0.04 0.04 0.04 Si content 0.21 0.52 0.83 0.21 0.52 0.21 0.52 Property Smoke density, DS-4 510 217 279 778 553 560 592 Transmission 29.4 18.7 16.4 90.0 89.7 89.1 89.7 Haze 104 104 104 0.51 0.48 1.13 1.43 having 81 mol % ester units (PC-Ester1) on smoke density. Table 7 and FIG. 6 show that for the different SiPC types, similar improvements in DS-4 values are achieved, independent of the SiPC architecture. In particular, DS-4 values are in the same range for the different SiPC types at the same silicon content. At a silicon content of 0.21 wt. %, DS-4 values of 300 to 400 are obtained for SiPC1 (Example 38), SiPC2 (Example 32) and SiPC4 (Example 43), all measured according to ISO5659-2 at 3 mm thickness at 50 kW/m². At a silicon content of 0.52 wt. %, DS-4 values of 200 to 280 are obtained for SiPC1 (Example 39), SiPC2 (Example 34) and SiPC4 (Example 44), all measured according to ISO5659-2 at 3 mm thickness at 50 kW/m².

Results show that the siloxane content in the polydimethylsiloxane/bisphenol A polycarbonate copolymer has no significant influence on the smoke density when compared at the same silicon content in the final formulation, comparing SiPC1 (20 wt. % D45) and SiPC2 (6 wt. % D45).

Similarly, the D-length of the siloxane block does not have a significant influence on the smoke density when compared at the same silicon content in the final formulation, comparing SiPC1 (20 wt. % D45) and SiPC4 (20 wt. % D90), as well as SiPC3 (D-length of 10 units, but also a different content).

In all cases, DS-4 values can be achieved close to or below the HL-2 thresholds for EN45545 R1 or R6 applications (DS-4<300 at 50 kW/m²), depending on the SiPC content in the composition, provided the other requirements (e.g. heat release) are also met.

Examples 47-53 (Table 7 and FIG. 5) show that the effects on smoke density reduction of PC-Ester 1 are different for siloxane oils compared to SiPC copolymers. Polydimethyl siloxane (PDMS) oil also gives improvements in DS-4, but is less efficient. For example, higher silicon contents are needed to achieve a DS-4 value meeting the HL-2 requirements for R1 or R6 applications (DS-4<300 at 50 kW/m²). Polymethylphenylsiloxane (PMPS) oil as well as octaphenylcyclotetrasiloxane (OPCTS) does not improve smoke density of PC-Ester1 copolymer as efficient as PDMS oil, demonstrating the need for an aliphatic siloxane type (PDMS) instead of aromatic siloxanes. This is highly unexpected, as for other flame properties, such as UL V-0 compliance, the siloxane of choice are typically phenyl based (like octaphenylcyclotetrasiloxane or polyphenylmethylsiloxane) rather than PDMS.

PDMS oil may have the disadvantages of opaqueness and potential for bleach out, due to inherent immiscibility with polycarbonate and its copolymers. Nevertheless, PDMS oil can be formulated to PC-Ester1 to obtain a composition that has a smoke density close to or below the HL-2 threshold for EN45545 R1 or R6 applications (DS-4<300 at 50 kW/m²), provided the other requirements (e.g. heat release) are also met.

Examples 54-58

Examples 54-58 demonstrate the effect of adding polydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 mol % siloxane units (SiPC2) to linear bisphenol A polycarbonate resin (PC1). Formulations and results are shown in Table 8.

TABLE 8 Unit CEx 54 CEx 55 CEx 56 CEx 57 CEx 58 Component PC1 Wt. % 100.00 87.45 74.95 49.95 SiPC2 Wt. % 12.50 25.00 50.00 100.00 Irgafos 168 Wt. % 0.05 0.05 0.05 Si content Wt. % 0 0.26 0.52 1.04 2.08 Property Smoke density, — 979 513 569 716 935 DS-4

Comparative Examples 54 and 58 show that both linear bisphenol A polycarbonate resin (PC1) and polydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. % siloxane units (SiPC2) have relatively high smoke densities measured according to ISO5659-2 at 3 mm thickness at 50 kW/m². However, as shown in comparative Examples 55-57, when relatively low amounts of SiPC2 are added to PC1, the smoke density values decrease significantly. Nonetheless, the decrease in DS-4 is rather limited and the values remain rather high, and the formulations containing PC1 and SiPC2 do not meet the HL2 requirements for EN45545 R1 or R6 applications (DS-4<300 at 50 kW/m²).

Examples 63-77

These examples demonstrate that the effect of polydimethylsiloxane/bisphenol A polycarbonate copolymer addition on smoke density reduction is also applicable to compositions containing bisphenol A diphosphate (BPADP) as well.

Examples 63-72

Examples 63-72 demonstrate that the addition of BPADP together with polydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. % siloxane units (SiPC2) to poly(phthalate-carbonate) copolymer having 81 mol % ester units (PC-Ester1) improves the smoke density, the heat release and the melt flow of PC-Ester 1-containing compositions, while retaining ductile multiaxial impact at +23° C. and 0° C. Results and formulations are shown in Table 10.

Table 10 demonstrates that BPADP has a positive effect on the smoke density as it further reduces DS-4 values of a composition containing PC-Ester1 and SiPC2, but not BPADP, from 308 (Example 63) to values between 150 and 280 (Examples 64-72), all measured according to ISO 5659-2 on 3 mm thick plaques at 50 kW/m², which is significantly below the 300 threshold for HL2 compliance for R1 or R6 applications, for compositions containing PC-Ester1, SiPC2 and BPADP. The data also shows that BPADP has a positive effect on MAHRE, as it reduces MAHRE of a composition containing PC-Ester1 and SiPC2, but not BPADP, from 129 kW/m² (Example 63) to values below the 90 kW/m² threshold (Examples 64-72) for HL2 compliance for R1 or R6 applications after different amounts of BPADP are added, all measured according to ISO5659-2 at 3 mm thickness at 50 kW/m². MAHRE values of these compositions are even close to the 60 kW/m² threshold for HL3 compliance for R1 and R6 applications. These properties are achieved for a broad range of PC-Si2 loadings (5-30 wt. % based on the total polymer content) and BPADP loadings (3.5 to 15 wt. % based on the total composition). As such, the addition of BPADP to compositions containing SiPC2 and PC-Ester1 results in compositions that can be fully compliant with the HL2 requirements for R1 and R6 applications according to EN45545, which requires a combination of DS-4 values below 300 measured according to ISO5659-2 at 3 mm thickness at 50 kW/m² and MAHRE values below 90 kW/m² measured according to ISO5660-1 at 3 mm thickness at 50 kW/m², provided that the other required properties meet the selection criteria as well. Therefore, these compositions can be used in these types of applications.

Furthermore, BPADP also improves the melt flow, as can be seen in the increase in MVR and decrease in MV for Examples 64-72 compared to Example 63. The MVR and MV values can be tuned by optimizing the SiPC2 to PC-Ester1 ratio and/or the BPADP content of the composition. As such, MVR values between 4 and 12 cc/10 min can be achieved at 300° C. at 1.2 kg, which typically allow both injection molding of parts and extrusion of sheet.

These compositions have heat properties not exceeding those of regular PC with Vicat B120 values below 140° C., as low as 113° C., which would allow forming of parts at conventional forming temperatures for PC.

The addition of BPADP does not significantly reduce the multiaxial impact energy properties, since all samples retain energy levels above 100 J at 23° C. and 100%

TABLE 10 Component Unit CEx 63 Ex 64 Ex 65 Ex 66 Ex 67 Ex 68 Ex 69 PC-Ester1 Wt. % 88.07 84.92 83.12 81.31 79.63 77.94 74.57 SiPC2 Wt. % 9.79 9.44 9.24 9.04 8.85 8.66 8.29 Coated TiO2 Wt. % 2.00 2.00 2.00 2.00 2.00 2.00 2.00 Carbon black Wt. % 0.10 0.10 0.10 0.10 0.10 0.10 0.10 Irgafos 168 Wt. % 0.05 0.05 0.05 0.05 0.05 0.05 0.05 BPADP Wt. % 0.00 3.5 5.5 7.50 9.38 11.3 15 SiPC2/PC- % 10 10 10 10 10 10 10 Ester1 ratio Smoke density, — 308 178 184 194 243 205 217 DS-4 Heat release, kW/m² 129 NA NA 58 65 62 69 MAHRE Vicat B120 ° C. 174 NA NA 137 132 126 114 MAI +23° C., J 141 NA¹ NA¹ 102 NA¹ 130 121 Energy MAI, +23° C., % 100 NA² NA² 100 NA² 100 100 ductility MAI, 0° C., J 130 NA¹ NA¹ 83 103 112 102 energy MAI, 0° C., % 100 NA² NA² 100 100 100 75 ductility MVR, 300° C., Cm³/10 min 1.9 2.1 2.6 4.5 5.7 6.9 10.5 1.2 kg MV, 300° C., Pa · s * * * 573 375 301 235 1500 s⁻¹ Component Ex 69a Ex 69b Ex 70 Ex 71 Ex 72 Ex 72a Ex 72b Ex 72c PC-Ester1 74.54 67.76 84.10 73.00 66.40 71.45 63.60 59.85 SiPC2 15.81 22.59 4.42 15.48 22.12 15.16 23.00 23.00 Coated TiO2 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 Carbon black 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 Irgafos 168 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 BPADP 7.50 7.50 9.38 9.38 9.38 11.25 11.25 15.00 SiPC2/PC- 17.5 25 5 17.5 25 17.5 25 28 Ester1 ratio Smoke density, 157 186 206 179 177 215 184 274 DS-4 Heat release, 61 NA 65 66 73 NA 66 NA MAHRE Vicat B120 136 134 133 130 127 124 124 113 MAI +23° C., 127 113 129 130 123 129 134 121 Energy MAI, +23° C., 100 100 100 100 100 100 100 100 ductility MAI, 0° C., 85 96 118 104 115 119 115 126 energy MAI, 0° C., 100 100 100 100 100 100 100 100 ductility MVR, 300° C., 4.9 5.5 5.2 6.2 7.1 7.6 7.5 11.2 1.2 kg MV, 300° C., 374 343 394 328 289 284 272 207 1500 s⁻¹ ¹It is Ex pected that the multiaxial impact energy will be above 100 J, as all tested compositions with higher BPADP loadings have higher energy values. ²It is Ex pected that the ductility will be 100% as the compositions with higher BPADP loadings have been tested to have ductility of 100%. *Not measurable ductility, as measured according to ISO 6603 on 3.2 mm thick disks. Most samples retain 100% ductility even at 0° C., except the sample with the highest BPADP loading (Example 69, 15 wt. % BPADP), which has 75% ductility. This demonstrates that ductility is retained, even at relatively high BPADP loadings up to 11 and even 15 wt. %. As such, compositions containing SiPC2, PC-Ester1 and BPADP have a good combination of full HL2 compliance for R6 applications (smoke density and heat release), sufficient melt flow for molding of large and complex parts and retention of good practical impact properties. An optimal combination of these properties can be achieved upon proper formulation, which makes these compositions suitable for train interior parts that fully comply with R6 HL-2 requirements.

Examples 73-75

Examples 73-75 show that relatively small quantities of linear bisphenol A polycarbonate (PC4) can be added to compositions containing polydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. % siloxane units (SiPC2) and poly(phthalate-carbonate) copolymer having 81 mol % ester units (PC-Ester1), for instance to improve impact or flow, without deteriorating smoke density too much.

The formulations and the results are shown in Table 11.

TABLE 11 Component Unit Ex73 Ex74 Ex75 PC-Ester1 Wt. % 67.75 57.40 47.40 SiPC2 Wt. % 22.60 23.00 23.00 PC4 Wt. % 10.00 20.00 Coated TiO₂ Wt. % 2.00 2.00 2.00 Carbon black Wt. % 0.10 0.10 0.10 Irgafos 168 Wt. % 0.05 0.05 0.05 BPADP Wt. % 7.50 7.50 7.50 Property Smoke density, DS-4 — 186 244 266 MAI +23° C., Energy J 113 123 126 MAI, +23° C., ductility % 100 100 100 MAI, 0° C., energy J 96 128 136 MAI, 0° C., ductility % 100 100 100 MVR, 300° C., 1.2 kg Cm³/10 min 5.5 6.6 9.6 MV, 300° C., 1500 s⁻¹ Pa.s 343 293 243

Examples 74-75 show that the addition of small quantities of linear bisphenol A polycarbonate (PC2) to a composition containing BPADP, polydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. % siloxane units (SiPC2) and poly(phthalate-carbonate) copolymer having 81 mol % ester units (PC-Ester1) gives an increase in smoke density (DS-4 values of 244 and 246 for Examples 74 and 75, all measured according to ISO5659-2 at 3 mm thickness at 50 kW/m²) compared to the same composition without PC3 (DS-4 value of 186, measured according to ISO5659-2 at 3 mm thickness at 50 kW/m²). However, the increase is relatively minor and the DS-4 values still remain below the HL2 threshold (DS-4<300 at 50 kW/m²) for R1 or R6 applications.

The addition of PC2 to the composition results in a significant improvement in melt flow as evidenced by the increase in MVR (from 5.5 cc/10 min for Example 73 to 6.6 cc/10 min and 9.6 cc/10 min for Examples 74 and 75 respectively) and decrease in MV (from 343 Pa·s for Example 73 to 293 Pa·s and 243 Pa·s respectively for Examples 74 and 75).

Furthermore, the addition of PC2 to the composition also results in an improvement in practical impact properties, as the multiaxial impact energy at all measured temperatures increases for Examples 74 and 75 compared to Example 73.

As such, the addition of small quantities of linear bisphenol A polycarbonate (PC2) can be used to further improve the property profile of the compositions containing BPADP, polydimethylsiloxane/bisphenol A polycarbonate copolymer (SiPC2) and poly(phthalate-carbonate) copolymer (PC-Ester1), including melt flow and practical impact, while retaining the excellent smoke density properties of these compositions without the linear bisphenol A polycarbonate.

Examples 76-77

Examples 76-77 show the effect of changing the poly(phthalate-carbonate) copolymer type (PC-Ester2 instead of PC-Ester1) in compositions containing polydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. % siloxane units (SiPC2), BPADP and poly(phthalate-carbonate) copolymer.

The formulations and the results are shown in Table 12.

TABLE 12 Component Unit Ex76 Ex77 PC-Ester1 Wt. % 70.58 SiPC2 Wt. % 23.53 23.53 PC-Ester2 Wt. % 70.58 Coated TiO2 Wt. % 2.00 2.00 Carbon black Wt. % 0.10 0.10 Irgafos 168 Wt. % 0.05 0.05 BPADP Wt. % 3.75 3.75 Property Smoke density, DS-4 — 194 206

Examples 76 and 77 show that comparable smoke density values are obtained when PC-Ester1 (Example 76, DS-4 of 194 at 50 kW/m²), which contains 81 mol % ester groups, is replaced with PC-Ester2 (Example 77, DS-4 of 206 at 50 kW/m²), which contains 60 mol % ester groups. As such, effects observed in the previous examples are not limited to PC-Ester1 alone, but are also applicable to alternative types of the poly(phthalate-carbonate) copolymer.

Example 79

Example 79 demonstrates that the addition of BPADP together with polydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. % siloxane units (SiPC2) to poly(phthalate-carbonate) copolymer having 81 mol % ester units (PC-Ester1) improves the smoke density, the heat release, the flame spread, and the melt flow of PC-Ester 1-containing compositions, while retaining ductile multiaxial impact at +23° C. and 0° C. Results and formulations are shown in Table 13.

TABLE 13 Components, wt. % Unit Ex79 PC-Ester1 Wt. % 67.75 SiPC2 Wt. % 22.60 Coated TiO2 Wt. % 2.00 Carbon black Wt. % 0.10 Irgafos 168 Wt. % 0.05 BPADP Wt. % 7.50 Property Ds-4 ISO 5659-2 — 186 MAHRE ISO 5660-1 kW/m² 58 CFE ISO 5658-2 kW/m² 21.2 MVR, 300° C., 1.2 kg Cc/10 min 5.5 MV, 300° C., 1500 s⁻¹ Pa.s 343 MAI +23° C., Energy J 113 MAI, +23° C., ductility % 100 MAI, 0° C., energy J 96 MAI, 0° C., ductility % 100 Vicat B120 ° C. 135

Table 13 demonstrates that compositions containing BPADP, PC-Ester1 and SiPC2 have smoke density Ds-4 values of 186 measured according to ISO5659-2 at 3 mm thickness at 50 kW/m² and MAHRE values of 61 kW/m² measured according to ISO5660-1 at 3 mm thickness at 50 kW/m². As such, these compositions can be fully compliant with the HL2 requirements for R6 applications according to EN45545, which requires a combination of DS-4 values below 300 at 50 kW/m² and MAHRE values below 90 kW/m² at 50 kW/m². Therefore, these compositions can be used in these types of applications. MAHRE values of these compositions are even close to the 60 kW/m² at 50 kW/m² threshold for HL3 compliance for R1 and R6 applications.

Furthermore, these combinations have an excellent combination of melt flow, as indicated by the MVR values of 5.5 cc/10 min and retain excellent multiaxial impact properties, as indicated by the 100% ductility in multiaxial impact testing at +23° C. and 0° C. The flow can be further tuned by optimizing the SiPC2 to PC-Ester1 ratio and/or the BPADP content of the composition. As such, compositions containing SiPC2, PC-Ester1 and BPADP have a good combination of full HL2 compliance for R6 applications (smoke density and heat release), sufficient melt flow for molding of large and complex parts and retention of good practical impact properties. An optimal combination of these properties can be achieved upon proper formulation, which makes these compositions suitable for train interior parts that fully comply with R6 HL-2 requirements.

The composition further has a critical heat flux at extinguishment (CFE) of 21.2 kW/m², exceeding the threshold for HL2 or HL3 requirements for R1 applications, which both require a value at or above 20 kW/m². As such, combined with the MAHRE and Ds-4 values described above, these materials are also suitable for Hazard Level 2 (HL-2) (Ds-4<300 at 50 kW/m², CFE>20 kW/m² and MAHRE <90 kW/m² at 50 kW/m²) in European Railway standard EN-45545 class R1 applications. This combined with the flow and impact properties of these compositions makes these compositions excellent candidates for train interior parts that fully comply with R1 HL-2 requirements.

Example 78

Example 78 demonstrates that, similarly to Examples 63-77, the addition of BPADP together with polydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. % siloxane units (SiPC2) also improves smoke density and heat release of PPP-BP/BPA copolymer, while maintaining good transmission and haze properties. Results and formulations are shown in Table 13.

TABLE 13 Component Unit Ex 78 PPP-BP/BPA Wt. % 89.68 SiPC2 Wt. % 5.00 IRGANOX 1076 Wt. % 0.04 TINUVIN 329 Wt. % 0.20 Irgafos 168 Wt. % 0.08 BPADP Wt. % 5.00 Property Smoke density, DS-4 — 166 Heat release, MAHRE kW/m² 80 Transmission % 85.8 Haze — 1.97

Table 13 shows that the addition of both BPADP and SiPC2 to PPP-BP/BPA copolymer results in a combination of low smoke density (DS-4 of 166 measured according to ISO5659-2 at 3 mm thickness at 50 kW/m²) and low heat release (MAHRE of 80 kW/m², measured according to ISO5660-1 at 3 mm thickness at 50 kW/m²). Both values are below the HL2 thresholds for R6 applications for DS-4 (<300 at 50 kW/m²) and MAHRE (<90 kW/m² at 50 kW/m²), which makes these compositions fully with the HL2 requirements for R6 applications according to EN45545.

Furthermore, transmission is still relatively high upon addition of small amounts of SiPC2 ((85.8%) and haze is still relatively low (1.97), which allows to make compositions that both are compliant with the HL2 requirements for smoke density and heat release for R6 applications according to EN45545 and still have acceptable optical properties to be suitable for transparent applications, as well as diffuse, translucent and opaque colors, which can be tuned via a colorant package. Again, in general, transparent compositions can be tuned by the architecture of the polydimethylsiloxane/bisphenol A polycarbonate copolymer.

Examples 79-86

These examples demonstrate the effect of TiO₂ addition on smoke density reduction to compositions containing polydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. % siloxane units (SiPC2), poly(phthalate-carbonate) copolymer having 81 mol % ester units (PC-Ester1) and bisphenol A diphosphate (BPADP).

TABLE 14 Unit Ex 79 Ex 80 Ex 81 Ex 82 Ex 83 Ex 84 Ex 85 Ex 86 Component PC-Ester1 Wt. % 74.57 77.94 81.31 64.95 76.46 79.83 83.21 66.53 SiPC2 Wt. % 8.29 8.66 9.04 21.65 8.50 8.87 9.25 22.18 Coated TiO2 Wt. % 2.00 2.00 2.00 2.00 Carbon black Wt. % 0.10 0.10 0.10 0.10 Irgafos 168 Wt. % 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 BPADP Wt. % 15 11.25 7.50 11.25 15 11.25 7.50 11.25 SiPC2/PC-Ester1 % 10 10 10 25 10 10 10 25 ratio Property Smoke density, DS-4 — 217 205 194 184 309 326 289 316

A comparison of compositions with similar BPADP loading and SiPC2/PC-Ester1 ratio with and without TiO₂ shows that TiO₂ addition has a beneficial effect on the smoke density, comparing Examples 79 (DS-4 of 217) and 83 (DS-4 of 309), Examples 80 (DS-4 of 205) and 84 (DS-4 of 326), Examples 81 (DS-4 of 194) and 85 (DS-4 of 289) and Examples 82 (DS-4 of 184) and 86 (316), all measured according to ISO5659-2 at 3 mm thickness at 50 kW/m². Therefore, TiO₂ can be added to the composition to further improve the smoke density compared to the composition without TiO₂.

Examples 40-45

These comparative examples show that meeting the smoke density and heat release requirements of the EN45545 standard is not possible with regular flame retardant polycarbonate/acrylonitrile-butadiene-styrene blends and flame retardant polycarbonate resins. Formulations and results are shown in Table 13.

TABLE 13 Unit CEx 40 CEx 41 CEx 42 CEx 43 CEx 44 CEx 45 Component PC1 % 0 64.83 51.84 87.55 0 46.78 PC2 % 0 34.59 47.53 0 0 0 PC3 % 87.40 0 0 0 0 0 PC105B % 0 0 0 12.00 0 1.00 SiPC2 % 0 0 0 0 92.5 46.78 KSS % 0 0 0.03 0 0 0.25 Rimar % 0 0.08 0 0 0 0.08 Octaphenylcyclotetrasiloxane % 0 0.10 0 0 0 0 BPADP % 8.00 0 0 0 7.50 5.00 PTFE % 0.20 0 0 0 0 0 ABS R360 % 4.00 0 0 0 0 0 Standard additives % 0.40 0.40 0.60 0.35 0 0.12 Property Smoke density, DS-4 — 1320 1123 1320 1320 610 814 Heat release, MAHRE kW/m² 140 NA NA NA 153 211

Comparative example 40 is an example of a flame retardant polycarbonate/acrylonitrile-butadiene-styrene (PC/ABS) blend. The composition has the maximum measurable smoke density value (DS-4) of 1320 at 50 kW/m² and a heat release (MAHRE) of 140 kW/m² at 50 kW/m², which do not meet the EN45545 rail standard (2013) thresholds for R1 or R6 applications for smoke density (DS-4<600 for HL-1, DS-4<300 for HL2 and DS-4<150 for HL3, all at 50 kW/m²) and also do not meet the EN45545 rail standard (2013) thresholds for heat release (MAHRE <90 kW/m² for HL2 and MAHRE <60 kW/m² for HL3, all at 50 kW/m²). Therefore, flame retardant polycarbonate/acrylonitrile-butadiene-styrene (PC/ABS) blends are not suitable for seat components or claddings requiring meeting HL2 or HL3 requirements of the EN45545 standard.

Comparative examples 41 to 43 are examples of flame retardant bisphenol A polycarbonate resins. All compositions have high smoke density values (Ds-4) above 1000 at 50 kW/m², which do not meet the EN45545 rail standard (2013) thresholds for R1 or R6 applications for smoke density (DS-4<600 for HL-1, DS-4<300 for HL2 and DS-4<150 for HL3, all at 50 kW/m²) at any hazard level. Therefore, flame retardant polycarbonate resins are not suitable for seat components or claddings requiring meeting HL2 or HL3 requirements of the EN45545 standard.

Comparative examples 44 to 45 are examples of flame retardant poly(carbonate-siloxane) resins. All compositions have high smoke density values (Ds-4) above 600 at 50 kW/m², which do not meet the EN45545 rail standard (2013) thresholds for R1 or R6 applications for smoke density (DS-4<600 for HL-1, DS-4<300 for HL2 and DS-4<150 for HL3, all at 50 kW/m²) at any hazard level. Furthermore, these compositions have heat release (MAHRE) values above 150 kW/m² at 50 kW/m² which do not meet the EN45545 rail standard (2013) thresholds for heat release (MAHRE <90 kW/m² for HL2 and MAHRE <60 kW/m² for HL3, all at 50 kW/m²). Therefore, flame retardant poly(carbonate-siloxane) resins are not suitable for seat components or claddings requiring meeting HL2 or HL3 requirements of the EN45545 standard.

Examples 46-47

These comparative examples show that meeting the smoke density and heat release requirements of the EN45545 standard is possible with certain high heat polymers, but that these polymers do not have a suitable property profile for rail interior applications. Formulations and results are shown in Table 14.

TABLE 14 Component Unit CEx 46 CEx 47 PEI Wt. % 100 0 PPSU Wt. % 0 100 Property Smoke density, DS-4 76 67 Heat release, MAHRE kW/m² 43 15 MVR, 300° C., 1.2 kg Cc/10 min Cannot be Cannot be measured measured MV, 300° C., 1500 s−1 Pa.s Cannot be Cannot be measured measured MAI, RT, ductility % 0 0 Glass transition temperature ° C. 216 220

Comparative examples 46 and 47 show that both PEI and PPSU have very low smoke density (Ds-4) values around 60-70 and low heat release (MAHRE) values of 43 and 15 kW/m² respectively at 50 kW/m². As such, these resins are fully compliant with the HL2 or HL3 requirements for R1 and R6 applications according to EN45545 for smoke density (DS-4<300 for HL2 and DS-4<150 for HL3, all at 50 kW/m²) and heat release (MAHRE <90 kW/m² for HL2 and MAHRE <60 kW/m² for HL3, all at 50 kW/m²).

However, these resins both have limited practical impact properties, as indicated by their 0% ductility in MAI testing at room temperature. Furthermore, due to their high glass transition temperatures of 216 and 220° C. respectively, the melt flow is limited, such that MVR and MV values cannot be measured at 300° C., which makes these resins less suitable for molding of large and complex parts, using conventional tooling for PC/ABS and PC resins, which have glass transition temperatures of 150° C. and lower, depending on the composition. Furthermore, the high glass transition temperatures of these resins make them very difficult to form using for instance thermoforming.

As such, despite meeting the HL2 or HL3 requirements for R1 and R6 applications according to EN45545 for smoke density (DS-4<300 for HL2 and DS-4<150 for HL3, all at 50 kW/m²) and heat release (MAHRE <90 for HL2 and MAHRE <60 for HL3, all at 50 kW/m²), these resins are less suitable for molding or forming of rail interior applications.

The singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. “Or” means “and/or.” The endpoints of all ranges directed to the same component or property are inclusive and independently combinable. The suffix “(s)” as used herein is intended to include both the singular and the plural of the term that it modifies, thereby including at least one of that term (e.g., “colorant(s)” includes at least one colorant). “Optional” or “optionally” means that the subsequently described event or circumstance can or cannot occur, and that the description includes instances where the event occurs and instances where it does not. Unless defined otherwise, technical and scientific terms used herein have the same meaning as is commonly understood by one of skill in the art to which this invention belongs.

As used herein, a “combination” is inclusive of blends, mixtures, alloys, reaction products, and the like. Compounds are described using standard nomenclature. For example, any position not substituted by any indicated group is understood to have its valency filled by a bond as indicated, or a hydrogen atom. A dash (“-”) that is not between two letters or symbols is used to indicate a point of attachment for a substituent. For example, —CHO is attached through carbon of the carbonyl group.

As used herein, the term “hydrocarbyl” and “hydrocarbon” refers broadly to a substituent comprising carbon and hydrogen, optionally with 1 to 3 heteroatoms, for example, oxygen, nitrogen, halogen, silicon, sulfur, or a combination comprising at least one of the foregoing; “alkyl” refers to a straight or branched chain, saturated monovalent hydrocarbon group; “alkylene” refers to a straight or branched chain, saturated, divalent hydrocarbon group; “alkylidene” refers to a straight or branched chain, saturated divalent hydrocarbon group, with both valences on a single common carbon atom; “alkenyl” refers to a straight or branched chain monovalent hydrocarbon group having at least two carbons joined by a carbon-carbon double bond; “cycloalkyl” refers to a non-aromatic monovalent monocyclic or multicylic hydrocarbon group having at least three carbon atoms, “cycloalkenyl” refers to a non-aromatic cyclic divalent hydrocarbon group having at least three carbon atoms, with at least one degree of unsaturation; “aryl” refers to an aromatic monovalent group containing only carbon in the aromatic ring or rings; “arylene” refers to an aromatic divalent group containing only carbon in the aromatic ring or rings; “alkylaryl” refers to an aryl group that has been substituted with an alkyl group as defined above, with 4-methylphenyl being an exemplary alkylaryl group; “arylalkyl” refers to an alkyl group that has been substituted with an aryl group as defined above, with benzyl being an exemplary arylalkyl group; “acyl” refers to an alkyl group as defined above with the indicated number of carbon atoms attached through a carbonyl carbon bridge (—C(═O)—); “alkoxy” refers to an alkyl group as defined above with the indicated number of carbon atoms attached through an oxygen bridge (—O—); and “aryloxy” refers to an aryl group as defined above with the indicated number of carbon atoms attached through an oxygen bridge (—O—).

Unless otherwise indicated, each of the foregoing groups can be unsubstituted or substituted, provided that the substitution does not significantly adversely affect synthesis, stability, or use of the compound. The term “substituted” as used herein means that at least one hydrogen on the designated atom or group is replaced with another group, provided that the designated atom's normal valence is not exceeded. When the substituent is oxo (i.e., ═O), then two hydrogens on the atom are replaced. Combinations of substituents and/or variables are permissible provided that the substitutions do not significantly adversely affect synthesis or use of the compound. Unless otherwise indicated, exemplary groups that can be present on a “substituted” position include, but are not limited to, cyano; hydroxyl; nitro; azido; alkanoyl (such as a C₂₋₆ alkanoyl group such as acyl); carboxamido; C₁₋₆ or C₁₋₃ alkyl, cycloalkyl, alkenyl, and alkynyl (including groups having at least one unsaturated linkages and from 2 to 8, or 2 to 6 carbon atoms); C₁₋₆ or C₁₋₃ alkoxy groups; C₆₋₁₀ aryloxy such as phenoxy; C₁₋₆ alkylthio; C₁₋₆ or C₁₋₃ alkylsulfinyl; C1-6 or C₁₋₃ alkylsulfonyl; aminodi(C₁₋₆ or C₁₋₃)alkyl; C₆₋₁₂ aryl having at least one aromatic rings (e.g., phenyl, biphenyl, naphthyl, or the like, each ring either substituted or unsubstituted aromatic); C₇₋₁₉ alkylenearyl having 1 to 3 separate or fused rings and from 6 to 18 ring carbon atoms, with benzyl being an exemplary arylalkyl group; or arylalkoxy having 1 to 3 separate or fused rings and from 6 to 18 ring carbon atoms, with benzyloxy being an exemplary arylalkoxy group.

All references cited herein are incorporated by reference in their entirety. While typical embodiments have been set forth for the purpose of illustration, the foregoing descriptions should not be deemed to be a limitation on the scope herein. Accordingly, various modifications, adaptations, and alternatives can occur to one skilled in the art without departing from the spirit and scope herein. 

What is claimed is:
 1. A railway component, wherein the component is a molded or extruded train seat component comprising a thermoplastic composition comprising, based on the total weight of the composition: 50 to 93 wt. % of a poly(bisphenol A carbonate)-co-(bisphenol phthalate ester); 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E has an average value of 2 to 200, wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein the component has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs.
 2. The railway component of claim 1, wherein the component is injection molded, and the thermoplastic composition has a melt volume flow rate of equal to or greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO
 1133. 3. The component of claim 1, wherein the component is extruded, and formed, and the thermoplastic composition having a Vicat B120 of less than 140° C. measured according to ISO
 306. 4. The railway component of claim 1, wherein the thermoplastic composition comprises from 4 to 20 wt. % of the poly(carbonate-siloxane) comprising from 1 to 10 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane), and wherein a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm.
 5. The railway component of claim 1, wherein the poly(bisphenol-A carbonate)-co-poly(bisphenol phthalate ester) comprises 75 to 85 wt. % of ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate in the ester units of 98:2 to 88:12.
 6. The railway component of claim 1, wherein the a poly(bisphenol-A carbonate)-co-poly(bisphenol phthalate ester) comprises 35 to 45 wt. % of carbonate units and 55 to 65 wt. % of ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate of 45:55 to 55:45.
 7. The railway component of claim 1, wherein E has an average value of 2 to
 60. 8. The railway component of claim 1, wherein the organophosphorus compound is an aromatic organophosphorus compound having at least one organic aromatic group and at least one phosphorus-containing group, or an organic compound having at least one phosphorus-nitrogen bond.
 9. The railway component of claim 8, wherein the organophosphorus compound of the thermoplastic composition is bisphenol A bis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate), tricresyl phosphate, a phenol/bi-phenol polyphosphate, or a combination comprising at least one of the foregoing.
 10. The railway component of claim 8, wherein organophosphorus compound containing a nitrogen-phosphorus bond is a phosphazene, phosphorus ester amide, phosphoric acid amide, phosphonic acid amide, phosphinic acid amide, tris(aziridinyl)phosphine oxide, a combination comprising at least one of the foregoing.
 11. The railway component of claim 1, wherein the thermoplastic composition further comprises 0.1 to 12 wt. % of TiO₂.
 12. The railway component of claim 1, wherein the thermoplastic composition further comprises 0.05 to 5.0 wt. % of a light diffuser additive comprising silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethyleneglycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing.
 13. The railway component of claim 1, wherein the thermoplastic composition further comprises 0.00002 to 5.0 wt. % of a colorant based on the total weight of the polymers in the thermoplastic composition.
 14. The railway component of claim 1, wherein the thermoplastic composition further comprises 5 to 20 wt. % of a bisphenol A polycarbonate.
 15. A railway component, wherein the component is an extruded or molded interior train cladding comprising a thermoplastic composition comprising 50 to 93 wt. % of a poly(bisphenol A carbonate)-co-(bisphenol phthalate ester) 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E has an average value of 2 to 200, wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein a molded sample of the thermoplastic composition has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², a critical heat flux at extinguishment (CFE) of equal to or greater than 20 kW/m² measured according to ISO 5658-2 on a 3 mm thick plaque, and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second according to ISO 6603 on 3.2 mm thick discs.
 16. The railway component of claim 15, wherein the component is injected molded, and the thermoplastic composition has a melt volume flow rate of 4 cc/10 min or higher measured at 300° C. under 1.2 kg force measured according to ISO
 1133. 17. The railway component of claim 15, wherein the component is extruded, and the thermoplastic composition has a Vicat B120 of less than 140° C. measured according to ISO
 306. 18. The railway component of claim 15, wherein the thermoplastic composition comprises from 4 to 20 wt. % of the poly(carbonate-siloxane) comprising from 1 to 10 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane), and wherein a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm.
 19. The railway component of claim 15, wherein the poly(bisphenol-A carbonate)-co-poly(bisphenol phthalate ester) comprises 75 to 85 wt. % of ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate in the ester units of 98:2 to 88:12.
 20. The railway component of claim 15, wherein the poly(bisphenol-A carbonate)-co-poly(bisphenol phthalate ester) comprises 35 to 45 wt. % of carbonate units and 55 to 65 wt. % of ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate of 45:55 to 55:45.
 21. The railway component of claim 15, wherein E has an average value of 2 to
 60. 22. The railway component of claim 15, wherein the organophosphorus compound is an aromatic organophosphorus compound having at least one organic aromatic group and at least one phosphorus-containing group, or an organic compound having at least one phosphorus-nitrogen bond.
 23. The railway component of claim 22, wherein the organophosphorus compound of the thermoplastic composition is bisphenol A bis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate), tricresyl phosphate, a phenol/bi-phenol polyphosphate, or a combination comprising at least one of the foregoing.
 24. The railway component of claim 22, wherein organophosphorus compound containing a nitrogen-phosphorus bond is a phosphazene, phosphorus ester amide, phosphoric acid amide, phosphonic acid amide, phosphinic acid amide, tris(aziridinyl)phosphine oxide, a combination comprising at least one of the foregoing.
 25. The railway component of claim 15, wherein the thermoplastic composition further comprises 0.05 to 5.0 wt. % of a light diffuser additive comprising silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethyleneglycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing.
 26. The railway component of claim 15, wherein the thermoplastic composition further comprises 0.00002 to 5.0 wt. % of a colorant based on the total weight of the polymers in the thermoplastic composition.
 27. The railway component of claim 15, wherein the thermoplastic composition further comprises 0.1 to 12 wt. % of TiO₂.
 28. The railway component of claim 15, wherein the thermoplastic composition further comprises 5 to 20 wt. % of a bisphenol polycarbonate.
 29. The railway component of claim 15, wherein the cladding is an interior vertical surface selected from room dividers, flaps, boxes, hoods and louvres; an interior door or lining for internal and external doors; a window insulation; a kitchen interior surface; an interior horizontal surface selected from ceiling paneling, flaps, boxes, hoods and louvres; a luggage storage area selected from overhead and vertical luggage racks, luggage containers and compartments; a driver's desk application selected from paneling and surfaces of driver's desk; an interior surface of gangways selected from interior sides of gangway membranes (bellows) and interior linings; a window frame; an optionally folding table with downward facing surface; an interior or exterior surface of air ducts, or a device for passenger information.
 30. The railway component of claim 29, wherein the cladding is a side wall, a front wall, an end-wall, a partition, a room divider, an interior door, a window insulation, a lining, a kitchen interior surface, a ceiling panel, an overhead or vertical luggage rack, a luggage container, a luggage compartment, a window frame, an optionally folding table with downward facing surface, or an information display screen.
 31. The railway component of claim 15, wherein the component is a partition, a room divider, an interior door or lining for internal and external doors, a window insulation, an overhead and vertical luggage rack, a luggage container and compartment, a window frame; an optionally folding table with downward facing surface; or a device for passenger information; and wherein the component has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm.
 32. The railway component of any one of claim 15, wherein the component is a partition, a room divider, an interior door or lining for internal and external doors, a window insulation, an overhead and vertical luggage rack, a luggage container and compartment, a window frame, an optionally folding table with downward facing surface, or a device for passenger information; and wherein the thermoplastic composition further comprises a light diffuser additive.
 33. A railway component, wherein the component is a molded or extruded train seat component, comprising a thermoplastic composition comprising, based on the total weight of the composition: 50 to 93 wt. % of a polycarbonate copolymer comprising bisphenol A carbonate units and units of the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to five C₁₋₁₀ alkyl groups, or C₁₋₄ alkyl; 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E has an average value of 2 to 200, wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein the component has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque, an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque, a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque, and a ductility in multiaxial impact of 100%, measured at 0° C. at an impact speed of 4.4 m/second according to ISO 6603 on 3.2 mm thick discs.
 34. The railway component of claim 33, wherein the component is injection molded, and the thermoplastic composition has a melt volume flow rate of equal to or greater than 4 cc/10 min measured at 300° C. under 1.2 kg force measured according to ISO
 1133. 35. The railway component of claim 33, wherein the component is extruded, and formed, and the thermoplastic composition having a Vicat B120 of less than 140° C. measured according to ISO
 306. 36. The railway component of claim 33, wherein the thermoplastic composition comprises from 4 to 20 wt. % of the poly(carbonate-siloxane) comprising from 1 to 10 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane), and wherein a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm.
 37. The railway component of claim 33, wherein R⁵ is phenyl.
 38. The railway component of claim 33, wherein E has an average value of 2 to
 60. 39. The railway component of claim 33, wherein the organophosphorus compound is an aromatic organophosphorus compound having at least one organic aromatic group and at least one phosphorus-containing group, or an organic compound having at least one phosphorus-nitrogen bond.
 40. The railway component of claim 39, wherein the organophosphorus compound of the thermoplastic composition is bisphenol A bis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate), tricresyl phosphate, a phenol/bi-phenol polyphosphate, or a combination comprising at least one of the foregoing.
 41. The railway component of claim 39, wherein organophosphorus compound containing a nitrogen-phosphorus bond is a phosphazene, phosphorus ester amide, phosphoric acid amide, phosphonic acid amide, phosphinic acid amide, tris(aziridinyl)phosphine oxide, a combination comprising at least one of the foregoing.
 42. The railway component of claim 33, wherein the thermoplastic composition further comprises 0.05 to 5.0 wt. % of a light diffuser additive comprising silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethyleneglycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing.
 43. The railway component of claim 33, wherein the thermoplastic composition further comprises 0.00002 to 5.0 wt. % of a colorant based on the total weight of the polymers in the thermoplastic composition.
 44. The component of claim 33, wherein the thermoplastic composition further comprises 0.1 to 12 wt. % of TiO₂.
 45. The railway component of claim 33, wherein the thermoplastic composition further comprises 5 to 20 wt. % of a bisphenol polycarbonate.
 46. A railway component, wherein the component is an extruded or molded interior train cladding comprising a thermoplastic composition comprising 50 to 93 wt. % of a polycarbonate copolymer comprising bisphenol A carbonate units and units of the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to five C₁₋₁₀ alkyl groups, or C₁₋₄ alkyl; 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E has an average value of 2 to 200, wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein a molded sample of the thermoplastic composition has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², a critical heat flux at extinguishment (CFE) of equal to or greater than 20 kW/m² measured according to ISO 5658-2 on a 3 mm thick plaque, and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs.
 47. The railway component of claim 46, wherein the component is injected molded, and the thermoplastic composition has a melt volume flow rate of 4 cc/10 min or higher measured at 300° C. under 1.2 kg force measured according to ISO
 1133. 48. The railway component of claim 46, wherein the component is extruded, and the thermoplastic composition has a Vicat B120 of less than 140° C. measured according to ISO
 306. 49. The railway component of any of claim 46, wherein the thermoplastic composition comprises from 4 to 20 wt. % of the poly(carbonate-siloxane) comprising from 1 to 10 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane), and wherein a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm.
 50. The railway component of claim 46, wherein R⁵ is phenyl.
 51. The railway component of claim 46, wherein E has an average value of 2 to
 60. 52. The railway component of claim 46, wherein the organophosphorus compound is an aromatic organophosphorus compound having at least one organic aromatic group and at least one phosphorus-containing group, or an organic compound having at least one phosphorus-nitrogen bond.
 53. The railway component of claim 52, wherein the organophosphorus compound of the thermoplastic composition is bisphenol A bis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate), tricresyl phosphate, a phenol/bi-phenol polyphosphate, or a combination comprising at least one of the foregoing.
 54. The railway component of claim 52, wherein organophosphorus compound containing a nitrogen-phosphorus bond is a phosphazene, phosphorus ester amide, phosphoric acid amide, phosphonic acid amide, phosphinic acid amide, tris(aziridinyl)phosphine oxide, a combination comprising at least one of the foregoing.
 55. The railway component of claim 46, wherein the thermoplastic composition further comprises 0.05 to 5.0 wt. % of a light diffuser additive comprising silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethyleneglycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing.
 56. The railway component of claim 46, wherein the thermoplastic composition further comprises 0.00002 to 5.0 wt. % of a colorant based on the total weight of the polymers in the thermoplastic composition.
 57. The railway component of claim 46, wherein the thermoplastic composition further comprises 0.1 to 12 wt. % of TiO₂.
 58. The railway component of claim 46, wherein the thermoplastic composition further comprises 5 to 20 wt. % of a bisphenol polycarbonate.
 59. The railway component of claim 46, wherein the cladding is an interior vertical surface selected from room dividers, flaps, boxes, hoods and louvres; an interior door or lining for internal and external doors; a window insulation; a kitchen interior surface; an interior horizontal surface selected from ceiling paneling, flaps, boxes, hoods and louvres; a luggage storage area selected from overhead and vertical luggage racks, luggage containers and compartments; a driver's desk application selected from paneling and surfaces of driver's desk; an interior surface of gangways selected from interior sides of gangway membranes (bellows) and interior linings; a window frame; an optionally folding table with downward facing surface; an interior or exterior surface of air ducts, or a device for passenger information.
 60. The railway component of claim 59, wherein the cladding is a side wall, a front wall, an end-wall, a partition, a room divider, an interior door, a window insulation, a lining, a kitchen interior surface, a ceiling panel, an overhead or vertical luggage rack, a luggage container, a luggage compartment, a window frame, an optionally folding table with downward facing surface, or an information display screen.
 61. The railway component of claim 46, wherein the component is a partition, a room divider, an interior door or lining for internal and external doors, a window insulation, an overhead and vertical luggage rack, a luggage container and compartment, a window frame; an optionally folding table with downward facing surface; or a device for passenger information; and wherein the component has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D1003 using the color space CIE1931 (Illuminant C and a 2^(∘) observer) at a thickness of 3 mm.
 62. The railway component of claim 46, wherein the component is a partition, a room divider, an interior door or lining for internal and external doors, a window insulation, an overhead and vertical luggage rack, a luggage container and compartment, a window frame, an optionally folding table with downward facing surface, or a device for passenger information; and wherein the thermoplastic composition further comprises a light diffuser additive.
 63. A railway component, wherein the component is a molded or extruded train seat component comprising a thermoplastic composition comprising, based on the total weight of the composition: 50 to 93 wt. % of a combination comprising (i) 5 to 50 wt. % of bisphenol A polycarbonate and (ii) 50 to 95 wt. % of a poly(bisphenol arylate) of the formula

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, C₁₋₁₂ alkenyl, C₃₋₈ cycloalkyl, or C₁₋₁₂ alkoxy, p and q are each independently 0 to 4, and x^(a) is a bridging group between the two arylene groups, and is a single bond, —O—, —S—, —S(O)—, —S(O)₂—, —C(O)—, a C₁₋₁₁ alkylidene of the formula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independently hydrogen or C₁₋₁₀ alkyl, or a group of the formula —C(═R^(e))— wherein R^(e) is a divalent C₁₋₁₀ hydrocarbon group, based on the weight of the combination; 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E has an average value of 2 to 200, wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein the component has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs.
 64. The railway component of claim 63, wherein the combination comprises (i) 35 to 45 wt. % of bisphenol A polycarbonate and (ii) 55 to 65 wt. % of a poly(bisphenol A-arylate ester).
 65. A railway component, wherein the component is an extruded or molded interior train cladding comprising a thermoplastic composition comprising, based on the total weight of the composition: 50 to 93 wt. % of a combination comprising (i) 5 to 50 wt. % of bisphenol A polycarbonate and (ii) 50 to 95 wt. % of a poly(bisphenol arylate ester) of the formula

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, C₁₋₁₂ alkenyl, C₃₋₈ cycloalkyl, or C₁₋₁₂ alkoxy, p and q are each independently 0 to 4, and X^(a) is a bridging group between the two arylene groups, and is a single bond, —O—, —S—, —S(O)—, —S(O)₂—, —C(O)—, a C₁₋₁₁ alkylidene of the formula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independently hydrogen or C₁₋₁₀ alkyl, or a group of the formula —C(═R^(e))— wherein R^(e) is a divalent C₁₋₁₀ hydrocarbon group, based on the weight of the combination; 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E has an average value of 2 to 200, wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein the component has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs.
 66. The railway component of claim 65, wherein the combination comprises (i) 35 to 45 wt. % of bisphenol A polycarbonate and (ii) 55 to 65 wt. % of a poly(bisphenol A arylate ester).
 67. A railway component, wherein the component is a molded or extruded train seat component comprising a thermoplastic composition comprising, based on the total weight of the composition: 75 to 96.5 wt. % of a poly(bisphenol A carbonate)-co-(bisphenol phthalate ester); 0.5 to 5 wt. % of a poly(siloxane) oil; 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein the component has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs.
 68. A railway component, wherein the component is an extruded or molded interior train cladding comprising a thermoplastic composition comprising, based on the total weight of the composition: wherein the component is a molded or extruded train seat component comprising a thermoplastic composition comprising, based on the total weight of the composition: 75 to 96.5 wt. % of a poly(bisphenol A carbonate)-co-(bisphenol phthalate ester); 0.5 to 5 wt. % of a poly(siloxane) oil; 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein the component has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs. 